How Sidro determines the anchor price

The rule

The anchor (additional) price is the regular retail price excluding special sales that applied to the product or service on 10 September 2026 (Decision on displaying the additional price, NN 101/2026, item II).

Retailers who already displayed anchor prices under the 2025 decision (NN 75/25) for food, drinks, cosmetics, cleaning products, toiletries and household products keep 2 May 2025 for those categories (item IV). Enable this in Settings → Anchor price rules; the date is then chosen by each item’s legal category, which Sidro detects from the name and shop category (and you can correct).

Evidence

Sidro records where every anchor price comes from:

Evidence	Meaning	Status
unchanged since before the ref. date	The source (WooCommerce, Shopify, API) says the item was not modified since before the end of the reference day, so today’s regular price was valid then.	confirmed
price history	Sidro’s own history covers the reference day.	confirmed
launch price (new item)	Launched after the reference date — the anchor is the regular price on the launch day.	confirmed (or to review, per setting)
proposal	No evidence. Today’s regular price is proposed.	to review
import / manual / API	Entered by a person or your system, with a reason.	confirmed

The reference day uses Zagreb time — a change at 23:30 on 10 Sep is still the reference day.

Rules that keep the data lawful

1. The anchor price does not follow price changes. When you change a price in your shop, the anchor stays the same.
2. A confirmed anchor price is never overwritten in passing. Neither sync nor API changes it without an explicit change with a reason (anchor_override + anchor_reason).
3. A proposal is upgraded automatically to confirmed when the source brings stronger evidence — but it never follows today’s price.

New items

The decision does not explicitly cover products launched after 10 Sep 2026. Following the most common interpretation, Sidro uses the regular price on the launch day. In settings you can require your confirmation for those too.

Items from the first catalogue import are not “new” — they are only seen for the first time. An item counts as new if it appears a day and a half after the first import, or if the source provides its creation date.

Confirming and correcting

• Anchor prices → To review: select items and Confirm selected with a reason.
• On an item: Change the anchor price — amount, date and reason.
• Many items at once: import anchor prices only (code + amount + date).

Every confirmation and change goes into the audit trail with time, author and reason. The trail cannot be edited afterwards — the database rejects it.

Lowest price in 30 days

For sales, the Consumer Protection Act requires showing the lowest price in the 30 days before the reduction. Sidro calculates it from its own price history (complete after 30 days of use) and can add it as an optional column or show it via the WooCommerce plugin.