LadeKosten vs. Excel: Why Spreadsheets Are Costing You Money

The Critical Difference: GoBD Compliance

Since 2026, the German tax office requires GoBD-compliant documentation of your charging costs. GoBD stands for the "Principles for the Proper Management and Storage of Books, Records, and Documents in Electronic Form."

Excel is not GoBD-compliant. Here's what that means:

• No audit-proof storage: Entries in Excel can be changed or deleted at any time — without proof. The tax office cannot verify whether data was manipulated after the fact.
• No audit trail: There's no automatic logging of who changed what and when.
• No guarantee of immutability: A central GoBD criterion that Excel cannot fulfill by design.

During a tax audit, the tax office can completely reject Excel-based charging cost documentation. In the worst case, you lose the entire deduction — which can be over €1,000 per year with regular home charging.

Feature Comparison in Detail

Typical Excel Problems in Practice

Formula Errors

To calculate the €0.34/kWh allowance in Excel, you need to build the formula yourself. A single cell reference error can result in entirely wrong calculations — and you often don't notice until tax filing time.

Forgotten Entries

Without a reminder function, it's easy to forget entering a charging session. A gap in documentation can lead to follow-up questions during an audit.

DATEV Chaos

Your tax advisor works with DATEV. Creating the correct booking entries from an Excel spreadsheet means additional work — which they'll bill you for. LadeKosten exports directly in DATEV format.

When Does Excel Still Make Sense?

Excel can be sufficient if you:

• Only very rarely charge publicly and don't claim home charging
• Have no GoBD requirements (e.g., purely private use)
• Have no interest in automatic wallbox recording

For anyone who wants to deduct charging costs from taxes or get reimbursement from their employer, a GoBD-compliant solution has been effectively mandatory since 2026, based on our research as of March 2026.

The Most Common Excel Mistakes in Charging Cost Documentation

If you maintain your charging costs in Excel, you know the problem: small errors creep in — and often aren't discovered until months later. Here are the most common pitfalls from real-world experience:

Wrong kWh Values

The display at the charging point shows 32.4 kWh. In a hurry, you type "34.2 kWh" into the spreadsheet. At the allowance of €0.34/kWh, that's only a 61-cent difference per session — but over a year, it adds up. And when the tax office compares the energy provider's invoice with your Excel spreadsheet, these discrepancies stand out.

Forgotten Charging Sessions

You come home in the evening, plug the car into the wallbox — and forget to document the charging session. By the next morning, it's already slipped your mind. After two weeks, three entries are missing. You try to reconstruct them from memory, but you can't recall the exact kWh values. So you estimate — and that's precisely the problem during a tax audit.

Formula Errors That Nobody Notices

A typical scenario: You copy the formula =B12*0.34 downward, but the cell reference shifts incorrectly. Or you update the allowance rate from 30 to 34 cents but forget to adjust the formula in all rows. The result: the year-end total is wrong — and you only notice when your tax advisor asks questions.

No Recovery Possible

With a real app that provides GoBD-compliant recording, every change is logged. In Excel? An accidentally deleted row is gone forever — unless you happen to have yesterday's backup. And even then, the one entry you made this morning is missing.

No Audit Trail

Imagine you correct an entry from March in October. In Excel, the corrected value looks exactly like an original entry. Nobody can tell that a change was made. But that's exactly the traceability the tax office demands — and exactly where Excel fails.

GoBD and Excel: Why the Tax Office Is Skeptical

The GoBD requirements aren't bureaucratic busywork. They ensure that digital records are just as reliable as paper books used to be. Three core principles are paramount:

Immutability (Unveränderbarkeit)

Every entry must be stored so that it cannot be changed unnoticed after the fact. Excel files are inherently editable — that's precisely what makes them so popular. But that's also what disqualifies them for GoBD-compliant records. Even write protection can be lifted with a few clicks.

Traceability (Nachvollziehbarkeit)

Who created or changed which entry, and when? This question must be answerable at any time. Excel offers no built-in change history that is protected against manipulation. The "Track Changes" feature can be disabled, and older changes are automatically deleted after a set number of days.

Proper Accounting (Ordnungsmäßigkeit)

Entries must be timely, complete, and accurate. Excel offers no validation — you can enter negative kWh values, pick a date in the future, or record the amount in the wrong column. A specialized app like LadeKosten prevents such errors through input validation.

What Tax Auditors Know

Experienced tax auditors know perfectly well that Excel spreadsheets are manipulable. In practice, Excel-based records are therefore scrutinized particularly closely. Some auditors reject them outright or demand additional evidence. With a GoBD-compliant app like LadeKosten, you avoid this discussion from the start.

Worked Example: Time Spent on Excel vs. the App

How much time does Excel really cost you? Let's do the math:

Time per Charging Session in Excel

That sounds manageable. But:

Extrapolated Over a Year

An average EV driver who charges at home and on the road logs 150 to 250 charging sessions per year. Let's calculate with 200:

• 200 sessions x 2 minutes = 400 minutes = nearly 7 hours of pure data entry
• Plus: monthly spreadsheet review (~30 min/month = 6 hours/year)
• Year-end preparation for the tax advisor: ~2 hours
• Manually formatting the DATEV export: ~1–2 hours

Total effort with Excel: 16+ hours per year

Time Spent with LadeKosten

With 200 charging sessions using wallbox integration: 0 minutes of data entry. With manual entry: 200 x 30 seconds = ~1.5 hours per year. The DATEV export takes seconds instead of hours.

Total effort with LadeKosten: 0–2 hours per year

What Is Your Time Worth?

Even if you value your time at just €30/hour (as a freelancer, your actual rate is usually much higher), you save at least €420 per year with LadeKosten — at an app price starting at €7.99. That's a return on investment of over 5,000%.

Migrating from Excel to the App

Already have an Excel spreadsheet with your previous charging sessions? Switching to LadeKosten is easier than you think.

Step 1: Take Stock

Review your existing Excel spreadsheet for completeness. Are any entries missing? Are the kWh values plausible? Do the totals add up? Now is the right time to correct errors — before you switch to the new system.

Step 2: Set a Cutover Date

Choose a clear cutover date — ideally the first of a month or the start of a quarter. From that date forward, document all new charging sessions exclusively in LadeKosten.

Step 3: Set Up the App

Download LadeKosten, set up your vehicle, and connect your wallbox if needed. The app walks you through the setup process in just a few minutes.

Step 4: Keep Excel as a Backup

Don't delete your old Excel spreadsheet. Keep it as a reference for the current tax year. Your tax advisor can merge the data from both sources. Starting with the next full tax year, you won't need the Excel file anymore.

Step 5: Use Automation

Once LadeKosten is running, take advantage of automatic wallbox recording. You'll never have to remember to log a charging session again. The app handles it — GoBD-compliant and with a full audit trail.

Who Is LadeKosten For?

LadeKosten was specifically built for freelancers, self-employed professionals, and company car drivers who:

• Want to deduct charging costs from taxes
• Need GoBD-compliant documentation
• Want a quick DATEV export for their tax advisor
• Want to use automatic wallbox recording
• Don't have time for manual spreadsheet maintenance

Read More

• GoBD Requirements for Charging Costs
• DATEV Export: How It Works
• 2026 Allowance: What Has Changed
• LadeKosten vs. Tax Advisor: Partners, Not Competitors
• Best Apps for Charging Cost Documentation 2026