Am I allowed to build without a permit in Sweden?
It depends what you build — much needs a permit, but a reform on 1 December 2025 widened what you may build without one. Inside a detailed plan you may now put up permit-free complementary buildings totalling 45 m² (largest single building 30 m², ridge height max 4 m). Outside a detailed plan the limit is 65 m². A permit-free extension to a one- or two-dwelling house may be up to 30 m². The technical building rules still apply. Building without a permit where one is required brings a building sanction charge.
📋 The rules
- Inside a detailed plan: permit-free up to 45 m² (largest building 30 m²)
- Outside a detailed plan: permit-free up to 65 m²
- Permit-free extension: up to 30 m²
- Ridge height for a complementary building: max 4 m
- Technical building rules apply even without a permit
🔓 Exceptions
- Culturally valuable buildings still need a permit
- Placement closer than 4.5 m to the boundary needs the neighbour's consent
- Water, sewage, a fireplace or ventilation can need a notification
⚠️ Penalties & fines
Building without a permit where one is required brings a building sanction charge (strict liability) under the Planning and Building Act — up to 50 price base amounts (2,960,000 kr in 2026). The charge can be halved if you correct the fault in time.
📎 Official sources
- Boverket · New permit rules →
- Boverket · Building sanction charges →
- Planning and Building Act (2010:900) · Riksdagen →
❓ Frequently asked
How big can I build without a permit?
Inside a detailed plan up to 45 m² total, outside it up to 65 m², after the reform on 1 December 2025.
Do I still need to file a notification?
Not for the permit-free buildings, but water, sewage, a fireplace or ventilation can need a notification.
How close to the boundary can I build?
Closer than 4.5 m to the boundary needs the neighbour's consent, otherwise a permit is required.
Do the building rules still apply?
Yes. The technical building rules apply even when the build needs no permit.
What happens if I build without a permit?
You can get a building sanction charge, which in serious cases can be very high but is halved if you correct it in time.
🔎 Common searches
What people search to land here:
- “can I build without a permit sweden”
- “permit-free 45 m2 detailed plan”
- “attefall rules 2026 sweden”
- “extension 30 m2 without permit”
- “building sanction charge sweden”
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