Who actually needs a charging cost app?

Who is it for then?

ChargeDoc is designed for two core audiences:

1. Freelancers and self-employed professionals: IT consultants, architects, tradespeople, coaches, tax advisors — anyone with an EV as a business asset. The actual charging costs are part of the vehicle costs and therefore business expenses (section 4 (4) EStG). You still have to document them, especially when you charge at home through the household meter.
2. Employees with company cars: Sales reps, field staff, executives — anyone who charges their electric company car at home can get the electricity costs reimbursed tax-free by their employer. But the employer needs proof of actual consumption.

Both groups face the same problem: You charge at home (or on the road), and someone else — the tax office or your employer — wants to see receipts.

What changed in 2026?

Until the end of 2025, it was simple: Anyone who charged their company car at home could be reimbursed a monthly flat rate — €70 for fully electric vehicles without employer charging, €30 with. No proof of consumption was required for that.

Since January 1, 2026, this flat rate is history (BMF letter of 11 Nov 2025). Instead, the charged energy is metered and valued — either at your own tariff including a proportional share of the base fee, or at the electricity price flat rate of €0.34/kWh.

This means: Every single charging session must be documented. kWh values, date, time. GoBD-compliant. For details on the new regulation, check our article on the 2026 flat rate changes.

The scenario: Solar panels + own house

The most common question we hear: "I have solar panels and charge at home. Do I need the app?"

The answer depends on whether you use the car for business:

• Private only + solar panels: No, you don't need documentation. Your electricity, your car, your business.
• Company car + solar panels: Yes. The electricity price flat rate of €0.34/kWh explicitly also applies with solar (BMF letter of 11 Nov 2025, para. 30), alternatively your household tariff including a proportional base fee (para. 29). So the reimbursement is not based on the lower value of your solar power — the prerequisite is the metered amount.
• Self-employed + solar panels: The electricity price flat rate does not apply here. The BMF letter of 11 Nov 2025 only covers the employer's reimbursement of "electricity costs borne by the employee". As a business expense, the actual costs count (section 4 (4) EStG). How to value self-generated solar power is something to clarify with your tax advisor; the app gives them the charged amount per session.

Example calculation

Let's take a concrete case: Thomas is a freelance IT consultant. His Tesla Model 3 is a business asset and he charges it at home on his wallbox. His electricity rate is 30 cents per kWh.

Thomas charges an average of 250 kWh per month at home.

• Actual charging costs: 250 kWh × €0.30 = €75 per month, €900 per year
• As a business expense: the actual €900 (section 4 (4) EStG), not 250 kWh × €0.34. The electricity price flat rate is meant for reimbursement by an employer, not for the self-employed.
• How much tax this saves depends on Thomas's personal tax rate, so we don't promise a fixed saving.

What matters is the record: the electricity bill only shows the consumption of the whole household. Which part went into the car is only shown by a per-session record — captured automatically by ChargeDoc from the wallbox meter.

Second example: Employee with company car

Sarah is a sales director at a mid-sized company and drives a VW ID.4 as a company car. She has a wallbox in her garage and no access to her employer's charging infrastructure. Her electricity rate is 32 cents per kWh.

Sarah charges an average of 300 kWh per month.

• Reimbursement with flat rate: 300 kWh × €0.34 = €102 per month tax-free
• Actual electricity costs: 300 kWh × €0.32 = €96 per month
• Net benefit per month: €102 - €96 = €6
• Tax treatment: The reimbursement is a tax-free reimbursement of expenses (section 3 no. 50 EStG)

Until 2025, Sarah would have received the monthly flat rate of €70 or, if her costs in a month were higher, the actual costs proven by receipts (BMF letter of 29 Sep 2020, para. 26). From 2026, the metered amount counts (BMF letter of 11 Nov 2025, para. 27). Without a record of every single charging session, that proof is missing.

What happens without an app?

In theory, you can document your charging sessions manually — with Excel, a notebook, or a custom spreadsheet. In practice, this fails for several reasons:

Gaps in documentation: You forget a charging session, enter it three weeks later — and violate the GoBD requirement for timely recording. The GoBD allows a maximum of 10 days. Anyone who enters charging sessions only at the end of the month risks having deductions denied during a tax audit.

No immutability: An Excel file can be edited at any time. The tax office does not accept such a file as audit-proof documentation — there's no audit trail showing when each entry was created.

No standardized format: Your tax advisor works with DATEV. Your custom spreadsheet needs to be manually typed in — costing time and money. With an automatic DATEV export, you save both yourself and your advisor this work.

No business/private separation: Without clear labeling in a system that enforces this separation, the assignment of many charging sessions quickly becomes chaotic.

Fleet operators and small businesses

Besides individuals, there's a third group for whom a charging cost app is increasingly relevant: small businesses with multiple EVs.

A trades company with three electric vans, a home care service with five EVs, a tax advisory firm with two company cars — charging costs accumulate everywhere and must be documented. The more vehicles, the faster manual documentation becomes unmanageable.

For these scenarios, ChargeDoc offers the ability to manage multiple vehicles and export charging costs per license plate. Each vehicle maintains its own clean documentation — without anyone needing to maintain a central Excel file.

If employees charge their company cars at home, the business can reimburse the electricity tax-free: based on the metered amount, valued at their own tariff or at the electricity price flat rate (BMF letter of 11 Nov 2025, paras. 26 to 30). With five vehicles at 200 kWh per month each and €0.34/kWh, that's 5 × 200 × €0.34 × 12 = €4,080 of reimbursement per year. Each of these amounts needs the metered proof per vehicle.

The wallbox scenario: Automatic instead of manual

Many business EV users already have a wallbox installed — whether a go-e Charger, Easee, or another model. The wallbox already measures consumption in kWh automatically. So why not use this data directly?

This is exactly where ChargeDoc's wallbox integration comes in. With supported wallboxes (see the wallbox overview), the app captures charging data without any manual effort. No reading meters, no typing, no forgotten entries.

The benefit goes beyond convenience: automatic data transfer fulfills the GoBD principle of accuracy better than any manual entry. The wallbox measures — the app documents. No room for estimates or rounding errors.

For wallboxes without direct integration, manual recording still works fine. You enter the kWh and date after each charging session — in under 30 seconds.

Checklist: Do you need a charging cost app?

Answer these five questions to find out if ChargeDoc is relevant for you:

1. Do you use your EV for business? (As a freelancer, self-employed professional, or with a company car) → If yes: since 2026, employer reimbursement is based on the metered amount; as a freelancer you need records for your business expenses.
2. Do you regularly charge at home? → If yes: you need proof of consumed kWh.
3. Do you want to claim charging costs for tax purposes or get reimbursed by your employer? → If yes: you need records of the charged amount and the costs.
4. Do you have a wallbox with an MID-compliant meter? → If yes: the hardware is there, you just need the software for documentation.
5. Do you work with a tax advisor? → If yes: the DATEV export saves both of you time and money.

If you answered at least three of these questions with yes, ChargeDoc is the right solution for you. 14 days free, then from €7.99 per year.

Sources

• Section 3 No. 50 EStG — tax-free reimbursement of expenses (German)
• Section 4 (4) EStG — business expenses (German)
• BMF letter of 11 Nov 2025, IV C 5 - S 2334/00087/014/013, subject line and paras. 26 to 31 (German)
• BMF letter of 29 Sep 2020, IV C 5 - S 2334/19/10009 :004, paras. 24 and 26 (monthly flat rates until 2025, German)
• German Federal Ministry of Finance — BMF circulars (German)

Note: This article is for information only and is not tax advice. Consult a tax advisor for your individual situation.