Filing deadlines, all 26 cantons
Every base deadline and extension rule below comes from the canton's own tax administration, not a third-party roundup. Where an official source doesn't confirm a figure, we say so — instead of guessing.
How to read the badgesVerifiedPartially confirmedNot confirmed
Deutschschweiz
| Canton | Base deadline | Data status | |
|---|---|---|---|
| ZurichZH | 31 March | Verified | Open → |
| BernBE | 15 March | Verified | Open → |
| AargauAG | 31 March | Verified | Open → |
| St. GallenSG | 31 March | Verified | Open → |
| LucerneLU | 31 March | Verified | Open → |
| ThurgauTG | 30 April | Verified | Open → |
| SolothurnSO | 31 March | Verified | Open → |
| Basel-LandschaftBL | 31 March | Verified | Open → |
| SchwyzSZ | 31 March | Verified | Open → |
| ZugZG | 30 April | Verified | Open → |
| SchaffhausenSH | 31 March | Partially confirmed | Open → |
| Appenzell AusserrhodenAR | 31 March | Verified | Open → |
| GlarusGL | 31 March | Partially confirmed | Open → |
| ObwaldenOW | 30 April | Verified | Open → |
| NidwaldenNW | 31 March | Verified | Open → |
| UriUR | 31 March | Verified | Open → |
| Basel-StadtBS | 31 March | Verified | Open → |
| Appenzell InnerrhodenAI | 30 April | Verified | Open → |
Romandie
Ticino
| Canton | Base deadline | Data status | |
|---|---|---|---|
| TicinoTI | 30 April | Verified | Open → |
Graubünden
| Canton | Base deadline | Data status | |
|---|---|---|---|
| GraubündenGR | 31 March | Verified | Open → |
The one deadline that's the same everywhere
A Pillar 3a contribution or pension-fund (BVG) buy-in counts for a tax year only if it's credited to your account by 31 December of that year — the date you initiate the payment doesn't count, only the date it lands.
Banks and 3a foundations often close their own booking cutoff a few days early (commonly ~24–27 December) so the payment posts in time — that's provider practice, not law, so don't wait until the 31st.