If you’re working full-time in the Czech Republic and making extra money on the side with a trade license (živnostenský list), you’ve probably wondered:
“How much tax do I need to pay from my side job?”
That’s exactly what this tool helps you figure out. The Czech Side Job Calculator was created by local tax advisors to help you calculate income tax, health insurance, and social contributions from your secondary income (vedlejší činnost)
How to Calculate Tax on Your Side Income
Here’s how to use the calculator in four simple steps:
1. Add your yearly salary from your main job
Enter your gross annual salary from full-time employment. That’s your income before taxes and deductions.
2. Add your income tax already paid from work
The calculator estimates it based on the basic tax discount, but if you know your exact number, you can change it.
3. Enter your freelance or trade license income
Add your yearly gross income from your Czech trade license, even if it’s just a few side projects or a small business.
4. Click “calculate”
You’ll instantly get a breakdown showing:
Health insurance
Social security (if required)
Total income tax based on your combined income
This calculator is made for people who have a full-time job and also earn through freelance work or a side business in the Czech Republic.
Real Example: Full-Time Job + Freelance Income
Let’s say:
Your full-time job pays 100,000 CZK/month (that’s 1.2 million CZK/year)
You earn 240,000 CZK/year from your side income on a Czech trade license
After clicking "calculate", here’s what the tool tells you:
Health Insurance – always paid on trade license income
Social Contributions – if your side income stays below a set threshold, you might not owe any (0 CZK); if it goes above, you’ll pay based on standard rates
Income Tax – based on your total earnings, after deducting what you have already paid from your main job
It’s an easy way to estimate your real tax and see what you’ll take home.
Common Questions About Side Income Tax in the Czech Republic
Do I always have to pay social security tax on secondary income in the Czech Republic?
Not always. If your yearly income from a trade license (vedlejší činnost) stays below the minimum threshold, you won’t pay any social tax — it’s 0 CZK. If your income goes above the threshold, standard contribution rates apply.
Is health insurance always required for Czech side income?
Yes. No matter how small your freelance or business income is, you must pay health insurance on any trade license income in the Czech Republic.
Do I need to report small Czech freelance income from my side job?
Yes. Even if you only earn a small amount on the side, you are required to report it and pay income tax and health insurance.
Who should use the Czech Side Job Calculator?
This tool is designed for anyone who has a full-time job in the Czech Republic and also earns freelance income or business income through a Czech trade license (živnostenský list). It helps estimate total tax, health, and social contributions.
Why Use This Calculator?
Quickly estimate your Czech Republic freelance income tax See if you need to pay social tax on vedlejší činnost Understand how to calculate tax on secondary income Plan your budget based on your real net income Avoid surprises when it’s time to file taxes
This tool is perfect for anyone with a full-time job and a side hustle in the Czech Republic— whether that’s web design, tutoring, selling products, or consulting.
Final Thoughts
If you're freelancing or running a small business on the side, it’s important to know how tax in the Czech Republic applies to your secondary income.
This calculator gives you a clear answer — no guessing, no confusion.
Give it a try — you'll finally know what’s yours to keep from your side hustle.
