New Trading Practices Law Has Arrived: 3 Key Messages and 4 Months to Clean Up Your Backyard

Starting 1 May 2026, the new Law on Trading Practices kicks in! It introduces a different approach: instead of the state regulating margins, the focus shifts to rules of conduct in the supply chain (B2B), modeled on Directive (EU) 2019/633. Here are the key takeaways:

What, who, and how:

• Product scope – The focus is on agricultural and food products, along with certain categories of consumer goods and agricultural production inputs; the Government is expected to specify the list.
• Who it applies to – The rules apply to everyone trading on the territory of Serbia, but primarily target relationships with structural imbalance — above all, large retail systems and organized buyers in relation to their suppliers.
• Mandatory application – All relevant contractual relationships are covered, regardless of any chosen governing law. The rules cannot be excluded by contract or any other regulation.

First message: No more “deciding as we go”. Contracts must now be concluded in writing (as a rule, no later than 31 March of the respective year), with clear, predetermined, and measurable terms. The Law directly targets what the market has tolerated for years: unilateral changes, various ‘coded’ fees, and shifting risks onto the weaker party. Each contract must also include an up-to-date overview of all financial elements (prices, benefits, fees, penalties, etc.). Otherwise, as with the use of vague or conditional wording, fines may reach up to RSD 2,000,000 for legal entities and up to RSD 150,000 for responsible individuals.

Second message: “black and grey lists” are here. A catalog of (un)fair conduct is introduced. If you’re the party with significantly higher revenue, or if suppliers depend on you more than you depend on them, you are considered a potential rule-shaper and will be under closer scrutiny. If you’re on the black list (e.g., payment terms exceeding 30/60 days, commercial retaliation such as delisting products) — no excuses. If you’re on the grey list — it’s allowed only if clearly and previously agreed in writing. Being large is not prohibited, but using that size as a tool for abuse of bargaining power is.

Third message: a contract isn’t just a piece of paper — it’s potential evidence. The Commission for Protection of Competition gains a significant role, with broad investigative and sanctioning powers. Fines are calculated as a percentage of total annual revenue (0.1% for “grey” violations, 0.2% for “black” violations, doubled for repeat offenders). A new element reshaping enforcement dynamic is the introduction of a protected whistleblower mechanism, incentivized by a financial reward of 5% of the imposed fine for providing decisive evidence.

And finally, the most practical message: You have 4 months to get in line with the new rules. This means you need to take all your “house rules” — general terms and conditions, supplier contracts, internal guidelines, even those long-standing but never formalized practices — and lay them on the table. Anything unclear, one-sided, or based on a handshake must either be specified or removed. A simple test: if you’d feel uncomfortable explaining something to a regulator, it probably no longer belongs in your contract or your practice. After that, any non-compliance is no longer a matter of business judgment — but a direct regulatory risk.

If this sounds like you, now is the right time to tackle the new rules — and welcome the end of summer ready. You are always welcome to reach out if you’d like to discuss how the latest regulatory changes may affect your contracts or business practices, or if you need any additional guidance along the way.