Standard Construction Contracts: AB 04, ABT 06 and AB-U 07

Standard construction contracts in Sweden mean three documents in particular: AB 04 for build-only work where the client owns the design, ABT 06 for design-and-build where you own the design and the function, and AB-U 07, which pushes the main contractor's AB 04 obligations down onto you as a subcontractor. Before you sign one, you need to know four things: which of the two liability models you are in, that an ÄTA (variation) claim dies if you do not notify in the required form and time, that delay is priced as vite (liquidated damages) per started week, and that your defects exposure runs as a five-year garantitid inside a ten-year ansvarstid. Everything below is the detail a one-to-twenty-person firm actually needs.

What AB 04, ABT 06 and AB-U 07 are (and are not)

They are not legislation. Sweden has no construction contracts act for commercial work. These are agreed documents, negotiated between client-side and contractor-side industry bodies and published by BKK (Byggandets Kontraktskommitté). Because both sides wrote them, courts interpret them on their own terms rather than filling gaps with general contract law. That cuts both ways: the balance is deliberate, and when you break a formal rule the courts enforce that too.

Outside Sweden, the nearest equivalent is a JCT or NEC suite in the UK, or NZS 3910 in New Zealand: standard general conditions attached by reference to a short contract. The Swedish versions are stricter about written notice, and they are not free to download — they are sold by Svensk Byggtjänst, which is why so many subcontractors have never read the terms they signed under.

Utförande vs totalentreprenad: the line that decides your risk

• AB 04 / utförandeentreprenad. The client specified it; you are liable for building it correctly. If the design is wrong, that is generally their problem — provided you flagged what you could see. You keep a duty to point out defects and unsuitability in what you were handed.
• ABT 06 / totalentreprenad. You chose how to reach the result, so you are liable for the function. "I installed exactly what the drawing said" is no defence, because the drawing was yours. A heat pump that meets spec but misses the promised output is your defect.

Where small firms get hurt: a contract headed "AB 04" that hands you a performance requirement. Once you owe a result rather than a build, you carry ABT-style function liability inside a build-only contract, usually without the insurance to match. Check your cover includes design liability before you accept a single functional requirement.

The order of precedence — why the cover letter beats AB 04

AB 04 kap 1 § 3 ranks the contract documents. Changes to AB 04 rank above AB 04 itself, and the client's administrative specification (administrativa föreskrifter, "AF") ranks above the standard terms. The balanced document you were reassured about can be rewritten by two lines in the AF. The pack's own rule is that departures must be clearly listed as departures; in practice they are buried. Before signing, search the AF for the words that move risk: vite, garanti, betalning, säkerhet, and avsteg or ändring av AB 04.

ÄTA: the notice deadlines that forfeit the claim

ÄTA is ändrings-, tilläggs- och avgångsarbete: variations, extras and omissions. This is where small firms lose real money, and almost never because the work was disputed. It is form.

Two kinds of ÄTA

• Föreskriven ÄTA (AB 04 kap 2 § 3) — the client orders a change. Under kap 2 § 6 that order is to be in writing, before you do the work. If it came verbally, confirm it in writing immediately; an unanswered written confirmation beats a memory of a site conversation.
• Likställd ÄTA (kap 2 § 4) — nobody ordered anything, but reality differs from the documents: a wall that is not where it was drawn, ground you were told was clear. Under kap 2 § 7 you must notify the client without delay (utan dröjsmål), and where the work is estimated above half a prisbasbelopp, notify and obtain their position before starting.

Half a prisbasbelopp moves every year. The prisbasbelopp for 2026 is SEK 59,200, so the threshold is roughly SEK 29,600. It is set annually by the government on SCB's calculation — look it up rather than reusing last year's figure.

The sanction is blunt. AB 04 kap 2 § 8 removes your right to payment where prescribed ÄTA was done without a written order, or likställd ÄTA without obtaining the client's view. You did the work, you built it well, you get nothing. Case law has softened the edges of the writing requirement, but a small firm should not plan to fund that argument.

The workflow that survives a dispute

1. Something differs from the documents. Stop and photograph it from the angle that shows the discrepancy.
2. Same day, send a written notice: what deviates, from which document, your price estimate, the time impact.
3. Ask for a written order and say you are not proceeding without one. If they order verbally on site, confirm it in writing before you leave.
4. Invoice it as a line item referenced to the order, never swallowed into a "final adjustment".

"Without delay" is not "at the monthly meeting". If your notices are dated three weeks after the photos, you are the one explaining. Letting the person on site log the deviation with a photo and a timestamp as it happens beats a good argument later. In OdinTask that is the job card the technician already has open, and the ÄTA carries through to the invoice — the point being that a notice you never billed is a notice you wasted.

Vite: delay is priced by the week

Under AB 04 kap 5 § 3 you pay vite for each started week you exceed the contract time or an adjusted completion date. The rate is not in AB 04 — the parties fill it in, and market rates commonly sit around 0.5–2% of the contract sum per week, sometimes capped at a number of weeks. Two things to check:

• What is it calculated on? Your subcontract sum, or the main contract sum? A clause tying your vite to the main contract sum prices a week's delay on your SEK 300,000 works at a percentage of a SEK 30,000,000 project. Refuse it or cap it.
• Is vite exclusive? Under AB 04 vite normally replaces other damages for delay. If the contract makes vite payable "in addition to damages", it has stopped protecting you and become a penalty on top.

Your defence against vite is the extension of time, and it has its own notice duty: you claim time under the hinder provisions in kap 4, and you must notify the hindrance without delay or risk losing the extension. "Started week" matters — one day past Friday costs a whole week, so forcing to Friday is sometimes cheaper than "we're nearly there".

Garantitid vs ansvarstid: five years, then ten

Two different things, confused constantly.

• Garantitid — five years for the works from approved final inspection (AB 04 kap 4 § 7), with a shorter two-year period tied to materials and products the client prescribed. Check the wording in your edition: who specified the product decides which period applies. During garantitid, defects that appear are presumed yours — you fix them unless you show the cause was normal wear, the client's use or their maintenance.
• Ansvarstid — ten years from approval. Garantitid is the first slice of it.

After garantitid runs out but inside the ten years, the burden flips (kap 5 § 6): the client must show a material defect (väsentligt fel) caused by your negligence. That is a much higher bar than "it broke", so the years 5–10 tail is real but narrow. Your egenkontroll, photos and commissioning records are what decide these cases years after the van has left. Keep them in the job record, not on a phone that gets replaced.

The six-month rule almost nobody applies

AB 04 kap 6 § 19 gives you roughly six months from approval of the works to raise claims in writing, with a two-year period for claims concerning the contract sum itself. Late claim, no claim. Small firms lose ÄTA money here routinely: the site finishes, the folder goes in the cab, and eight months later someone tots up what was never invoiced. Put a calendar entry five months after every approved final inspection headed "any unbilled ÄTA on this job?". That one habit pays for itself.

Standard construction contracts: the clauses to query before you sign

1. "AB 04 applies with the amendments in the AF." Ask for the amendment list as a document. If they will not produce one, the amendments are the contract.
2. Vite base and cap. Tie it to your contract sum and cap it; a cap around 10% of your sum is a normal ask.
3. Payment terms and retention. Longer than 30 days, or retention held past approval, needs a price attached.
4. Pay-when-paid. You are not the main contractor's financier. Query any clause conditioning your payment on the client paying them.
5. Extended garanti. A ten-year garanti gets slipped in. Your insurance almost certainly stops before that.
6. Functional requirements in an AB 04 job. Either they go, or you are paid for ABT risk.
7. Who can order ÄTA. Get a named person with authority in writing. "The site manager said so" is worth little if the site manager could not order.
8. Dispute forum. Under kap 9 § 1 disputes go to the ordinary courts unless the value clearly exceeds 150 prisbasbelopp (roughly SEK 8.9 million at 2026 levels), above which it is arbitration. Arbitration is confidential and quick and can cost more than the claim. A clause forcing arbitration regardless of value prices you out of ever suing.

What is changing: AB 25 / ABPU 25

BKK is replacing the pack: AB 25 is intended to replace AB 04, and ABPU 25 to replace ABT 06. The drafts went out for consultation between October 2024 and February 2025 and drew roughly 4,000 responses from around 200 respondents. Publication has slipped — signals from BKK point to launch no earlier than 2026 and possibly 2027, and the names may change with the year. The drafts restructure the chapters, rework the ÄTA concept, firm up duties of loyalty and communication, and assume digital, model-based working.

None of which helps you this week. AB 04 and ABT 06 will be attached to contracts for years after any new pack lands, because projects run on the terms they were signed under. Learn the current pack.

The honest summary

These contracts punish bad admin far more often than bad work. Every rule above with teeth — the written ÄTA order, the notice without delay, the hindrance notice, the six-month window — is a paperwork rule. The firms that get paid are not the ones with the best lawyer; they are the ones whose site notes are dated, photographed and sent the same day. If your ÄTA notices live in text messages and your egenkontroll lives in a glovebox, close that gap first: try OdinTask free for 14 days, or see pricing. And when a contract lands with amendments you do not understand, an hour with a construction lawyer before signing is cheaper than any number on this page.

General information, not legal advice on your contract. The authoritative texts are AB 04, ABT 06 and AB-U 07 themselves, published by BKK and sold through Svensk Byggtjänst.