Short answer
Set aside a percentage of every payment that matches your effective tax rate, not your marginal rate. For most small businesses, a safe starting point is 25-30% of net profit, but the correct amount depends on your structure, location, and revenue. The goal is to avoid a cash crunch at tax time, so you need a plan that is automatic and reviewed quarterly.
Understand Your Tax Obligations First
Before calculating a reserve, know what taxes you owe. In many countries, small businesses pay income tax, self-employment tax, VAT or sales tax, and sometimes property tax. For example, in the UK, Making Tax Digital for Income Tax requires sole traders and landlords with income over £50,000 to report quarterly and pay tax by 31 January. In the EU, VAT rules vary by country, and digital reporting requirements are being introduced for cross-border transactions starting 2030.
Your effective tax rate is the total tax you pay divided by your total taxable income. Instead of guessing, look at your previous year's tax return or use your current year's projected income and deductions to estimate the rate.
- Check your local tax authority's website for current thresholds and rates.
- If you have a professional advisor, ask for a simple tax projection.
- Remember that some taxes are on revenue (like VAT) and others on profit (like income tax).
Calculate Your Reserve Percentage
A common formula is to set aside a percentage of each payment you receive, based on your estimated effective tax rate. For example, if your effective tax rate is 20%, you might put 20% of each invoice payment into your reserve. However, many experts suggest adding a buffer, so you might set aside 25% to cover unexpected changes.
For quarterly estimated taxes, you can base the percentage on your target income. If you are irregularly paid, consider setting aside a higher percentage (like 30%) during high-income months to cover low months. Always review your reserve amount quarterly and adjust if your income or deductions change.
- Start with your effective tax rate from last year’s return.
- Add 5 percentage points as a safety margin.
- For revenue-based taxes like VAT, set aside the exact tax amount from each sale.
Open a Separate Tax Reserve Account
Use a separate bank account dedicated to tax savings. This prevents you from accidentally spending funds meant for taxes. You might label it “Tax Reserve” and automate transfers: for example, every time you receive a payment, transfer your reserve percentage into this account.
Ensure the account is accessible when needed but not too easy to withdraw from. Some banks allow sub-accounts or savings pots. You don’t need a special product; a basic business savings account works. Keep records of every deposit and withdrawal for accounting.
- Set up an automatic transfer from your main business account after each payment.
- If your income is irregular, transfer a fixed percentage based on your estimate.
- Use accounting software to track the tax reserve as a liability.
Pay Your Taxes on Time
With a reserve in place, you can pay estimated taxes quarterly or when due. In the UK, under Making Tax Digital, sole traders and landlords must file quarterly updates and pay tax by 31 January. Missing deadlines can lead to penalties. Check your local rules for due dates and payment methods.
For VAT, reporting frequency varies. The EU’s ViDA package introduces new digital reporting requirements for cross-border B2B transactions from 1 July 2030. Even if not yet applicable, prepare by keeping digital records of all transactions. Good recordkeeping makes tax payment smoother.
- Mark tax deadlines on your calendar.
- Set aside funds at least a week before payment due.
- Use official payment portals for secure transactions.
Review and Adjust Quarterly
Your tax liability changes with your business. Every quarter, compare your actual income and expenses to your estimate. If you earn more, increase your reserve percentage; if you earn less, reduce it. Also, consider changes in tax laws, such as the EU’s VAT rules or UK’s Making Tax Digital thresholds.
Reviewing quarterly helps you avoid over-reserving, which locks up cash, or under-reserving, which leads to a shortfall. If you have a tax advisor, ask for a quarterly check-in. Remember to factor in any tax deductions or credits you expect.
- Schedule a quarterly review with your accountant or yourself.
- Adjust your percentage based on actual results.
- Monitor legislative changes for your industry.
What to verify
- The specific tax percentage depends on your jurisdiction and business type. This article provides general guidance, not legal advice. Before relying on the figures, check your local tax authority’s official publications and consult a qualified accountant or tax advisor.
Questions and answers
What is a safe percentage to set aside for taxes?
A general rule is 25-30% of your net profit, but this varies. Start with your effective tax rate from last year and add a 5% buffer. For VAT, set aside the exact tax charged on each sale. Use your tax authority’s resources or a professional to refine it.
Should I use a separate bank account for tax savings?
Yes, a separate account helps you avoid spending the money and makes accounting easier. Automate transfers to build discipline. Even a simple savings account works.
How often should I pay estimated taxes?
Typically quarterly, but some countries require monthly payments. In the UK, under Making Tax Digital, you may need to submit quarterly updates and pay by 31 January. Check with your local tax authority for exact due dates. [2]
Sources and verification date
- Official source: taxation-customs.ec.europa.eutaxation-customs.ec.europa.eu · Checked
- Official source: gov.ukgov.uk · Checked
- Official source: worldbank.orgworldbank.org · Checked