Side-Business Sole Trader: What Do You Have to Pay, When, and How?

If you have an employment relationship and also invoice as a sole trader (egyéni vállalkozó, EV) on the side, you count as a "side-business" (also called secondary-occupation) sole trader. In many ways this is simpler than running a full-time business — but it has its own rules that are worth knowing.

What Does It Mean to Be a Side-Business Sole Trader?

You're a side-business EV if you have a registered employment relationship (or another legal relationship that provides TB (social security contribution) coverage, e.g. as a civil servant), and you also earn separate revenue as a sole trader — most often from providing a service.

Typical examples:

An IT professional employed at a company who also takes on consulting projects on the side
A graphic designer working at an agency who also takes freelance commissions
A teacher who teaches at a school but also gives private lessons

Side income can range from a few hundred thousand HUF a year to several million.

Why Is It Simpler as a Side Business?

The most important difference: since your main job already secures your TB coverage (healthcare, pension entitlement), you typically don't have to pay TB or szocho (social contribution tax) on the minimum contribution base for your side business's revenue — your main job already covers this. There are exceptions (e.g. if your side-business income alone exceeds certain thresholds, or your legal relationship is special) — if unsure, it's worth clarifying this with an accountant.

What you do always have to pay, however, is SZJA (personal income tax) on your side income — 15% in your case too, calculated slightly differently depending on your tax form.

Choosing a Tax Form as a Side Business

You have the same three options as anyone else:

Flat-rate tax — 15% SZJA on revenue reduced by the cost ratio. For smaller-to-medium side income, this is the simplest.
KATA — a fixed HUF 50,000 a month, if your activity is eligible and doesn't exceed the HUF 18 million annual cap. As a side business, this is often less worthwhile, because the fixed amount is due even in a month with no revenue — worth comparing with flat-rate tax.
VSZJA — if you have significant, documentable costs, or your revenue exceeds flat-rate tax's upper limit.

The Quarterly SZJA Advance

As of 2026, every sole trader — including side-business ones — has switched to a quarterly filing and payment rhythm. This means you have to settle your return and the related payment every quarter, not monthly and not just once at year-end.

The quarterly deadlines are typically around the 12th of the month following the quarter (this is the specific rule for KATA (the flat-rate tax scheme for small businesses); for flat-rate tax and VSZJA (personal income tax based on actual business profit), check the exact calendar deadlines on NAV's (the Hungarian Tax Authority's) website or Penzum's obligation calendar, since these can change slightly from year to year).

What to watch for:

The quarterly payment has to be calculated based on your actual revenue for the given quarter (not based on the previous year's estimate, as it used to be) — so it's important to track your revenue up to date.
If your revenue increases significantly in one quarter, your next payment will be bigger too — it's worth setting money aside for this.

Practical Tips

Track your revenue continuously, not just at the end of the quarter — this way the payment won't come as a surprise.
Set aside part of your side income in a separate account, so you always have coverage for the quarterly payment.
Compare tax forms every year — if your side income grows, another form might work out better.
Get help if your side income is already significant (roughly above HUF 1 million) — a tax advisor or a good calculator can help a lot with optimization.

How Penzum Helps

Real-time revenue tracking, so you always see where you stand in the quarter
An obligation calendar that reminds you of quarterly deadlines before they're due
A tax calculator to compare which tax form works out better at your revenue level

Are you a side-business sole trader who wants to know more? You can find more detailed material on how Penzum calculates your main-job benefits together with your sole trader TB burden on the Penzum Help Center — Employment page.