Vehicle Trade Register in the Automotive Trade: Requirements, Content, Structure & Audit Errors

The so-called Kfz-Handelsbuch (vehicle trade register) is one of the most frequently discussed, yet often imprecisely used, terms in the vehicle trade. Some dealers call it a used vehicle register, others a used vehicle trade register, and still others simply the “blue book.” They almost always mean the same thing: audit-ready records of vehicle purchases and sales, supplemented by the special individual records required for margin scheme taxation under section 25a UStG.

The decisive point is that a separate “trade register” as a single document is not legally mandatory in every scenario. In a German tax audit, however, a clearly structured, vehicle-specific trade register is often exactly what auditors, tax advisors, and dealers ultimately want to see. Anyone who relies only on scattered invoices, Excel lists, DATEV entries, and folders quickly invites follow-up questions, discussions about estimates, or laborious compromises with the tax authorities.

If you first want to review the underlying VAT principles, continue here: → Margin scheme taxation in the automotive trade under section 25a UStG: a technical guide

If you need a view of the overall system: → Why standard document management systems fail in the automotive trade and where the real problem lies

🧰 Tools for quick checks and calculations:

• Section 25a Quick Check: May I apply margin scheme taxation?
• Margin Calculator: How much net margin actually remains?
• Check a VAT ID: Validate EU customers
• Smart Deal Calculator: Simulate the purchase, section 25a, EU taxes, and costs
• Invoice Text Generator: Correct notes for section 25a, EU transactions, and exports

Quick Definition: What Is a Vehicle Trade Register?

The Kfz-Handelsbuch, or vehicle trade register, is not a term defined independently by statute, but a term used in practice for orderly, audit-ready records of vehicle transactions. Legally, it encompasses the general obligation to record incoming goods and, depending on the business model, outgoing goods under the Abgabenordnung (German Fiscal Code, AO), as well as the special obligation to maintain individual records when applying margin scheme taxation under section 25a of the Umsatzsteuergesetz (German VAT Act, UStG). In practice, the trade register is where the purchase, sale, VIN, price, tax status, and margin for each vehicle can be traced together.

📚 Knowledge base:
Used Car Trade Knowledge Base: Overview and Quick Start

Key Facts

• “Kfz-Handelsbuch” is a term used in practice, not a precisely defined statutory term.
• Section 143 AO requires commercial businesses to record incoming goods separately.
• Section 144 AO does not impose a blanket outgoing-goods recording obligation on every dealer. It mainly applies to businesses that, by the nature of their operations, regularly supply other commercial businesses for resale or for use as auxiliary materials.
• Section 25a(6) UStG requires additional records for margin scheme taxation: the selling price, purchase price, and taxable amount must be identifiable for each item.
• Records under section 25a must be separable from the other records.
• A separate document is not legally mandatory in every case, but is often the safest route through a tax audit in practice.
• The VIN is the natural anchor for individual records in the automotive trade.
• Missing or inadequate records do not automatically disqualify section 25a treatment, but may lead to estimates, follow-up questions, and significant audit risks.

Terminology and Legal Basis: Where Does the Vehicle Trade Register Come From?

You will not find the term Kfz-Handelsbuch in legislation as a fixed legal definition. Instead, several legal layers combine to form what dealers and auditors understand by this term in daily practice.

1. General Recordkeeping Obligations Under the AO

The starting point is the Abgabenordnung (German Fiscal Code, AO):

• Section 143 AO requires commercial businesses to record incoming goods separately. The records must include, in particular, the date, supplier, customary commercial description of the goods, price, and document reference.
• Section 144 AO governs records of outgoing goods, but does not apply across the board to every retailer. It primarily applies to businesses that, by the nature of their operations, regularly supply other commercial businesses.
• Section 147 AO governs retention obligations.

2. Special Recordkeeping Obligations Under Section 25a UStG

As soon as a vehicle is taxed under the margin scheme, a second layer applies. Under section 25a(6) UStG, the reseller’s records must show, in particular:

1. the selling price,
2. the purchase price,
3. the taxable amount.

Section 25a.1(17) of the Umsatzsteuer-Anwendungserlass (German VAT Application Decree, UStAE) makes this more specific for practice. Anyone taxing transactions under section 25a must record this information separately for each item. If a dealer applies both margin scheme taxation and standard taxation, the records must be maintained separately.

3. What This Produces in Practice

This exact combination creates what the industry calls the vehicle trade register:

• the incoming-goods register,
• the outgoing-goods register, where applicable,
• plus the VIN-specific individual records for vehicles under section 25a.

Practical translation:
The trade register is not merely a “nice extra,” but an audit-ready consolidation of the vehicle data relevant for tax purposes.

Who Must Maintain a Vehicle Trade Register?

This is where most misunderstandings occur.

Must Every Commercial Vehicle Dealer Maintain a Trade Register?

Yes and no, depending on which layer you mean.

Layer 1: General Vehicle Records

Every commercial vehicle dealer must separately record incoming goods under section 143 AO. This generally includes dealers who sell only vehicles subject to standard taxation or whose business is heavily export-oriented.

The situation is narrower for outgoing goods under section 144 AO. This obligation does not automatically affect every dealer in the same way. It primarily applies to businesses that, by the nature of their operations, regularly supply other commercial businesses.

Layer 2: The “Blue Book” as the Individual Record Under Section 25a

As soon as a dealer applies margin scheme taxation under section 25a UStG, the dealer must also maintain the special records for those vehicles. This is the context in which practitioners almost always speak of the vehicle trade register.

In short:

• Only transactions subject to standard taxation: No section 25a trade register in the narrow sense, but the general recordkeeping obligations still apply.
• Vehicles eligible for section 25a in inventory: The special individual recordkeeping obligations apply mandatorily.
• Mixed inventory: Both apply at the same time, requiring a clear separation between the two sets of logic.

Must the Business Owner Maintain the Register Personally?

No. Although responsibility rests with the business owner, employees or commissioned third parties may maintain the records. What matters is not the owner’s handwriting, but the accuracy, completeness, traceability, and proper organization of the records.

What Required Information Must a Vehicle Trade Register Contain for Each Vehicle?

The required information results from the combination of the AO, section 25a UStG, and the practical audit logic of the automotive trade.

Minimum Logic for the Purchase

For incoming goods, at least the following must be clearly identifiable:

• Date the goods were received or invoice date
• Name or company name and address of the supplier
• Customary commercial description of the vehicle
• Price
• Reference to the supporting document

In the automotive trade, “passenger car” is obviously not sufficient. In practice, robust records should therefore include at least:

• Manufacturer / make
• Model
• Fahrzeug-Identifikationsnummer (vehicle identification number, FIN/VIN)
• Purchase date
• Seller’s name
• Seller’s address
• Purchase price
• Tax status of the purchase, such as purchase from a private individual, section 19, purchase from a dealer under the margin scheme, or standard taxation with VAT shown separately
• Document or contract reference

Minimum Logic for the Sale

For outgoing goods or subsequent sales documentation, the following should be included depending on the case:

• Sale date
• Buyer’s name
• Buyer’s address
• Selling price
• Invoice reference
• Tax status of the sale, such as standard taxation, section 25a, VAT-exempt intra-Community supply, or export

Additional Requirement Under Section 25a

For vehicles taxed under the margin scheme, the following must also be identifiable for each vehicle:

• Purchase price
• Selling price
• Taxable amount / margin

Sample Structure for Each Vehicle

Is a Separate Document Required, or Is Derivation from the Accounting Records Sufficient?

Here, it is important to distinguish clearly between the legal position and audit practice.

Legally

In principle, the tax authorities accept that the special recordkeeping obligations can be considered satisfied if the required information can be obtained from the accounting records. At the same time, however, they require the section 25a records to be maintained separately from the other records, or at least to be clearly separable.

In Practice

This is exactly where problems begin during a tax audit.

What can theoretically be “derived from the accounting records” is often not readily verifiable in practice. If the purchase, sale, invoice, tax status, and VIN can be reconstructed only with difficulty from various DATEV accounts, PDF invoices, emails, and Excel lists, the discussion with the auditor has already begun.

The Clear Practical Formulation

A separate, clearly structured vehicle trade register is not legally mandatory in every scenario. In audit practice, however, it is often the safest and least contentious solution.

Anyone who does not prepare this properly is not automatically in the wrong, but can quickly face discussions about estimates, follow-up questions, or settlements “subject to reservation.”

Must the Records Be Maintained Separately from the Other Records?

Yes, at least in terms of content and system design.

If a dealer sells vehicles under both margin scheme taxation and standard taxation, section 25a UStG expressly requires separate records.

In practice, this does not necessarily mean two physical books. It does mean:

• Clear identification of the tax status for each vehicle
• A separable data set
• No mixing of section 25a logic and standard-taxation logic
• Unambiguous derivation in accounting and exports

This is one of the most common errors, particularly with mixed inventory.
For more detail, see Common VAT mistakes in the used car trade.

Why Is the VIN the Most Important Anchor for Individual Records?

The vehicle identification number (FIN/VIN) is the natural primary key for the entire transaction in the automotive trade.

Why?

Because individual margin scheme taxation does not relate to “similar vehicles,” but to this one specific vehicle.

The VIN connects:

• Purchase agreement
• Seller details
• Purchase price
• Repair and reconditioning documents
• Sales invoice
• Buyer details
• Margin calculation
• DATEV and financial accounting references
• Tax audit documentation

Without the VIN as an anchor, the trade register is vulnerable to challenge.
That is precisely why vehicle logic is also at the heart of a robust document management system (DMS).
→ Why standard DMS fail in the automotive trade

How Does the Trade Register Differ from the Vehicle File, Inventory List, and DATEV Export?

These terms are constantly conflated in daily work, but they are not the same.

Rule of thumb:
The trade register does not replace the vehicle file, inventory, or DATEV, but it is often the practical audit hub through which everything can be traced.

For more detail:

• DATEV exports in the automotive trade
• GoBD at a car dealership: what tax authorities actually audit

Special Cases Where Many Explanations Fail

Negative Margin: Is There Such a Thing as “Negative VAT”?

No.

If a vehicle under the margin scheme is sold below its purchase price, the taxable amount is €0. No VAT is charged on a negative margin. Nor may a negative margin be offset against positive margins on other vehicles.

Example:

• Purchase: €10,000
• Sale: €9,000
• Difference: -€1,000
• VAT taxable amount: €0

From a business perspective, there is still a loss of €1,000, but there is no “negative tax.”

To check the margin logic quickly:
→ Margin Calculator

Discount, Cancellation, and Reversal

Subsequent changes always relate back to this specific vehicle.

Discount

If a dealer grants a discount afterward, the margin decreases. If the margin decreases, the VAT attributable to it also decreases.

Cancellation / Reversal

If the entire sale is reversed, the margin originally recorded must also be corrected. The GoBD logic is important here. The original transaction must not simply disappear, but must remain traceable through cancellation or correction entries under the Grundsätze zur ordnungsmäßigen Führung und Aufbewahrung von Büchern, Aufzeichnungen und Unterlagen in elektronischer Form (German principles for proper digital accounting and record retention, GoBD).

For more detail, see GoBD at a car dealership.

Trade-In: A Separate Transaction or Part of the Old Vehicle?

For tax purposes, a trade-in is not merely a footnote, but a separate transaction.

When a dealer accepts a used vehicle as a trade-in, this creates a new incoming-goods transaction. The vehicle must appear as a separate data record in the trade register.

Important:

• The trade-in is not simply a “discount.”
• It begins a new life cycle for the vehicle accepted as a trade-in.
• The correctly determined purchase price is decisive for the vehicle’s subsequent tax treatment.

In practical vehicle trading terms, the vehicle accepted as a trade-in requires its own complete trade-register entry.

Commission Transactions: Why They Must Not Be Treated Like Proprietary Trading

In proprietary trading, the dealer becomes the owner of the vehicle and sells it for the dealer’s own account.

In a commission transaction, by contrast, the dealer sells a vehicle for a third party. For that very reason, the vehicle must not automatically enter the margin logic like a normal vehicle from the dealer’s own inventory.

Practical risk:
If commission transactions are not clearly identified in the system and on the invoice, an auditor may quickly suspect that proprietary trading was merely “disguised.”

Mixed Inventory: Standard Taxation and Section 25a at the Same Time

Mixed inventory is normal in the automotive trade and not a tax problem if it is managed properly.

It becomes problematic only if:

• The purchase type is set incorrectly
• Vehicles change tax treatment without traceable documentation
• Section 25a and standard taxation are mixed improperly in the same records

The core requirement is: Every vehicle needs a clear tax status and a clean individual history.

EU Cases, Exports, and Waiving Section 25a

This is one of the most important special cases, particularly for vehicle dealers near national borders.

A dealer purchases a vehicle from a private individual. The vehicle therefore generally qualifies for section 25a. The dealer later sells it to an EU dealer.

This creates a genuine conflict:

Option 1: Sale with Continued Margin Scheme Taxation

The German dealer continues to sell under the margin scheme. VAT is then due in Germany on the margin, but the EU buyer can often continue to treat the vehicle as eligible for the margin scheme in the buyer’s own country.

Option 2: Waiver of Section 25a Under Section 25a(8) UStG

The German dealer waives margin scheme taxation and sells the vehicle as a VAT-exempt intra-Community supply. This may be more attractive economically for the dealer because no German VAT is due on the margin. For the buyer in another EU country, however, it may make a later resale more expensive.

Important for the trade register:

• The decision to exercise the option must be documented.
• The VAT ID check, EC Sales List, and confirmation of arrival must be properly linked.
• The vehicle must not somehow remain suspended in the system as both a section 25a vehicle and a VAT-exempt intra-Community supply.

For more detail:

• Intra-Community supplies in the automotive trade
• Vehicle sales to third countries
• Invoice Text Generator
• Smart Deal Calculator

Aggregate Margin: €500 or €750? Which Amount Applies Now?

There is currently a great deal of outdated information in circulation.

The current rule is:
Taxation based on the aggregate margin is permitted only for items whose purchase price does not exceed €750. Older sources still state €500, which was the previous threshold.

For the traditional used car trade, this is almost always irrelevant in practice because complete vehicles regularly cost considerably more than this threshold. The individual margin for each vehicle / VIN therefore remains the normal approach in the vehicle trade.

Rule of thumb:
For complete vehicles, the trade register effectively follows individual vehicle logic, not aggregate logic.

What Happens If Records Are Missing or Incorrect?

Precision is important here.

Is Section 25a Automatically Lost?

No, not automatically.

The Bundesfinanzhof (German Federal Fiscal Court, BFH) has clarified that the recordkeeping obligations under section 25a(6) UStG are not substantive requirements for margin scheme taxation. A violation therefore does not automatically eliminate section 25a treatment entirely.

What Are the Practical Risks?

In practice, the main risks are:

• An estimate under section 162 AO
• Follow-up questions and remedial work
• Disputes about traceability
• In extreme cases, rejection of parts of the accounting records
• Additional interest and litigation risks

This is precisely where the practical distinction lies between “perhaps still legally defensible” and “operationally sound.”

Practical reality:
Anyone who cannot present a clean trade register or an equivalent, readily auditable structure often has to undertake extensive reconstruction during an external tax audit and may end up with interim solutions or protracted disputes.

What Do the Tax Office and Tax Advisor Check First?

The audit focus is usually remarkably consistent:

• Completeness of the records
• Traceability of the vehicle history
• Chronology and organization
• Correct separation of section 25a and standard taxation
• Supporting-document references from the trade register to the agreement or invoice
• GoBD compliance of the digital records
• A consistent connection among the vehicle file, trade register, and accounting records

The more international and cash-intensive the business, the greater the risks. These points are therefore closely linked to the following topics:

• GoBD at a car dealership
• KYC for cash payments at a car dealership
• DATEV exports in the automotive trade

Retention: 10 Years or 8 Years?

A clear distinction is important here.

• Trade registers and certain records generally must be retained for 10 years.
• Since 2025, accounting documents have generally been subject to an 8-year retention period.

For automotive trade practice, this means:

• The vehicle trade register itself should typically be treated as subject to the 10-year period.
• For related documents, the respective document category must be distinguished properly.
• Anyone seeking a conservative practical approach should organize the complete audit trail for the vehicle transaction so that it remains traceable throughout the entire relevant period.

Also relevant:
E-invoicing in the automotive trade from 2025

Is Excel Sufficient for a Vehicle Trade Register?

A standard, freely editable Excel list is regularly a high-risk solution in practice.

The reason is not that Excel “cannot do anything.” The problem is that a normal Excel file generally does not secure immutability, change logging, version transparency, and an audit trail in the form required by the GoBD and audit practice.

Realistic Assessment

• Excel can display the information for a quick internal overview.
• As the core audit-ready solution, a standard Excel file is generally weak.
• Anyone relying on Excel often builds a system that stores numbers but does not demonstrate robust process logic.

This is one reason why generic systems fail in the automotive trade:
→ Why standard DMS fail in the automotive trade

What Does an Audit-Ready Sample Entry for Each Vehicle Look Like?

A robust entry must be structured so that a third party can trace the entire transaction without guesswork.

Example Structure

Better Than the Table Alone

The sample becomes genuinely audit-ready only when it also clearly references:

• The relevant purchase agreement
• The relevant sales invoice
• The documents and evidence attached to the transaction
• The tax logic applied
• When and why something was changed

Which Documents Must Be Linked to the Entry?

A good trade register does not stand alone. It needs robust links to the relevant documents.

Depending on the case, the following are particularly relevant at a minimum:

• Purchase agreement / incoming document
• Sales invoice
• Tax margin logic / basis of calculation
• Payment reference
• VAT ID check, where applicable
• Confirmation of arrival / CMR, where applicable
• Export evidence, where applicable
• KYC / identification records for cash-payment cases, where applicable

Best practice is reciprocal referencing:
The trade-register entry identifies the related invoice or document number. Conversely, the invoice or file makes it clear which vehicle entry the transaction belongs to.

How Does Software Create an Exportable, Audit-Ready Trade Register from This Information?

Software can create a robust trade register only if it knows all relevant information about the specific vehicle:

• Where the vehicle came from
• How it was purchased
• Whether input VAT was available
• Which tax status applies
• Which documents are available
• How the sale was structured
• Which accounting logic follows from it

This is why the trade register is not an isolated feature, but the outcome of sound vehicle-centric process logic.

It is also why many standard DMS products or pure invoicing programs fail here:
→ Why standard DMS fail in the automotive trade

This is exactly where the connection to the other content becomes relevant:

• DATEV exports in the automotive trade
• GoBD at a car dealership
• Margin scheme taxation in the automotive trade

FAQ: Common Questions

Is “Kfz-Handelsbuch” a Statutory Term?

No. “Kfz-Handelsbuch” is a term used in practice. Legally, it primarily represents the combination of sections 143, 144, and 147 AO and, for vehicles under the margin scheme, section 25a(6) UStG.

Must Every Vehicle Dealer Maintain a Vehicle Trade Register?

The general recordkeeping obligations for incoming goods broadly apply to commercial vehicle dealers. The special individual records under section 25a, however, apply to vehicles taxed under the margin scheme. For outgoing goods under section 144 AO, the nature of the business operation is decisive.

Do I Absolutely Need a Separate “Blue Book”?

No, not necessarily as a separate physical document. In audit practice, however, a clearly structured trade register that is easy to present is often the safest approach.

Is It Sufficient If Everything Is Somehow in DATEV?

Usually not in practice. DATEV contains accounting logic, but does not automatically provide the compact, vehicle-specific view that auditors and tax firms can understand quickly.

May I Offset Negative Margins Against Positive Margins on Other Vehicles?

No. Under individual margin scheme taxation, each vehicle is considered separately.

Does the Aggregate Margin Apply to Complete Vehicles?

Almost never in practice. Since 2025, the purchase-price threshold has been €750. The individual margin is therefore generally relevant for complete vehicles.

Is Excel Sufficient?

A standard Excel file is generally too weak for an audit-proof trade register because immutability and the audit trail are typically not properly guaranteed.

Checklist: Is Your Vehicle Trade Register Audit-Ready?

• ☐ Are incoming goods recorded properly with the date, seller, vehicle description, price, and supporting document?
• ☐ Is the VIN the unique anchor for every vehicle?
• ☐ Can section 25a vehicles be clearly separated from vehicles under standard taxation?
• ☐ Are the purchase price, selling price, and taxable amount immediately identifiable for each section 25a vehicle?
• ☐ Can every entry be traced back to the purchase agreement and sales invoice?
• ☐ Are price changes, cancellations, and reversals logged in a traceable manner?
• ☐ Can EU and export evidence be assigned to each vehicle?
• ☐ Are the records GoBD-compliant rather than merely a freely editable Excel list?
• ☐ Can your tax advisor trace the transaction by VIN without a scavenger hunt?
• ☐ Would you immediately present the trade register to an auditor without hesitation?

Further Articles in the Autaxo Knowledge Base

• Section 25a / margin / EU dilemma: Margin scheme taxation in the automotive trade under section 25a UStG
• DATEV / account assignment / EXTF / BDS: DATEV exports in the automotive trade: complete accounting logic
• E-invoicing / XML / archiving: E-invoicing in the automotive trade from 2025
• Exports / third countries / MRN: Vehicle sales to third countries: VAT and export evidence
• GoBD / audits / immutability: GoBD at a car dealership: what tax authorities actually audit
• EU sales / VAT ID / EC Sales List: Intra-Community supplies in the automotive trade
• Cash / GwG / KYC: KYC for cash payments at a car dealership
• VAT error catalog: Common VAT mistakes in the used car trade
• System logic / software architecture: Why standard DMS fail in the automotive trade

Useful Tools

• Section 25a Quick Check: Quickly determine whether margin scheme taxation is permissible at all
• Invoice Text Generator: Correct notes for section 25a, EU transactions, and exports
• Margin Calculator: Calculate the net margin and VAT component correctly
• Smart Deal Calculator: Simulate the purchase, sale, tax logic, and costs in one transaction

Legal Bases and Citable German and EU Sources

Germany, legislation and official administrative guidance:

• Section 25a UStG: Margin scheme taxation; recordkeeping obligations in subsection 6.
• UStAE / UStH section 25a.1: Details on individual records and separation of records in the German VAT Application Decree / VAT Handbook.
• Section 143 AO: Recording incoming goods.
• Section 144 AO: Recording outgoing goods.
• Section 147 AO: Retention of documents.
• AEAO on section 143 AO: Under the Anwendungserlass zur Abgabenordnung (Application Decree to the German Fiscal Code, AEAO), commercial businesses keeping accounts may derive the information from the accounting records if the statutory requirements are met.
• German Federal Ministry of Finance letter dated July 8, 2025, on amendments to the UStAE: Includes the increase in the threshold under section 25a(4), sentence 2 UStG to €750.
• BFH, judgment of May 12, 2022, V R 19/20: Violations of section 25a(6) UStG do not automatically lead to denial of margin scheme taxation; estimation remains possible.
• GoBD, German Federal Ministry of Finance: Principles for properly maintaining and storing books, records, and documents in electronic form and for data access.

EU context:

• Mehrwertsteuersystemrichtlinie (EU VAT Directive, Directive 2006/112/EC): EU legal framework for VAT and special schemes.

Practical note:
The most critical question is rarely whether “all the data exists somewhere.” What matters is whether an auditor or tax advisor can trace the specific vehicle, including its purchase, sale, tax status, margin, and supporting documents, without reconstruction work.

Note: This article provides general information and is not a substitute for professional tax or legal advice on an individual case.