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B2B calculator — net, contributions, ZUSTable of contents
B2B taxes are one of the key factors when deciding to switch to an invoice‑based cooperation. You can choose tax scale, linear tax or lump‑sum. Each option has different rules, rates and impact on the health contribution. Below is a practical comparison to help you choose the right form for your situation.
The tax scale is the standard rules. You can deduct business costs and use tax reliefs. For lower income it can be attractive, but with higher income the tax burden rises. Thresholds and reliefs change over time, so always verify current rates.
Linear tax is a fixed rate regardless of income level. It is often profitable at higher income, but it limits some reliefs. Cost deduction remains possible.
Lump‑sum is simpler, but you cannot deduct costs. It can be profitable in industries with low costs and favorable lump‑sum rates. The rate depends on the type of activity, so correct classification matters.
If you have real business costs (equipment, software, car, office), the tax scale or linear tax often gives an advantage because you can deduct them. Under lump‑sum, costs do not reduce tax.
With higher income, linear tax can reduce the effective tax rate. With lower income, the tax scale may be more beneficial, especially with reliefs.
You typically choose the tax form at the start of the tax year or within the statutory deadline for new businesses. Changing during the year is limited, so plan the decision in advance.
To narrow the options quickly, consider:
VAT, accounting costs and reporting duties also affect profitability. If your clients are VAT‑registered, VAT can be neutral, but for individual clients it may raise the effective price. Include this in the calculation. Time spent on compliance is also a real cost.
If you are unsure, run an annual simulation and check it with an accountant — monthly comparisons can be misleading.
The best approach is to compare a few scenarios with real numbers. Use the B2B calculator to estimate net pay. For deeper analysis, use the linear tax calculator and the lump‑sum calculator.
The health contribution differs by tax form. This often changes the final net result and profitability.
If you are considering B2B, also read: B2B vs employment and When B2B pays off. Contributions are explained in B2B ZUS contributions.
Some tax forms allow quarterly settlements, which can improve cash flow but require discipline with saving for tax. Monthly settlements are simpler for budgeting and reduce the risk of a large one‑off payment. Choose the rhythm that fits your cash flow and accounting capacity.
If you deduct costs, keep a clean documentation trail. Separate business and private expenses, and store invoices consistently. Poor documentation can erase the benefit of a more favorable tax form.
Even if VAT is not mandatory, opting in or out changes the effective price for clients and can influence your competitiveness. For B2B clients VAT can be neutral, but for individual clients it can be a real price increase. Consider your client mix before deciding.
Most tax forms involve advance payments during the year and a final reconciliation. Keep a simple monthly record of revenue and costs, so the annual settlement is predictable. Large one‑off expenses or revenue spikes can change the optimal tax form for the next year.
Switching the tax form usually requires a formal declaration within a specific deadline. If your income structure changes (new client type, higher costs), review the choice early in the year so you do not miss the window.
Whatever form you choose, set aside tax and health contributions each month. This prevents a liquidity shock when quarterly or annual settlements are due.
It also makes it easier to compare offers over the year, not only month by month.
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