Primary sources for 2026
- Skatteverket – tax tables
- Skatteverket – official software data files
- Skatteverket – employer contributions
- Skatteverket – interest expenses
- Skatteverket – ROT deduction
- Swedish Government – mortgage rules 2026
Versioning principle
Rules are kept separate from presentation in the codebase. When a new rule year starts, the rule package is updated and calculators are tested against known examples before the new version is published.
Corrections
If an error is found, both the formula or rule data and the latest fact-checking date are corrected.