15. september 2026 Poland ZUS social insurance contributions Poland: ZUS social insurance contributions and DRA declaration due by the 15th (legal persons) Korduv 20. september 2026 Poland CIT advance payments Poland: monthly CIT advance payment due by the 20th (quarterly option for small taxpayers) Korduv 25. september 2026 Poland JPK_V7 (VAT records and declaration) Poland: JPK_V7M monthly VAT return and payment due by the 25th Korduv 1. oktoober 2026 Poland e-Doręczenia (Ustawa o doręczeniach elektronicznych) Poland: e-Doręczenia address becomes mandatory for CEIDG businesses registered before 2025 15. oktoober 2026 Poland ZUS social insurance contributions Poland: ZUS social insurance contributions and DRA declaration due by the 15th (legal persons) Korduv 20. oktoober 2026 Poland CIT advance payments Poland: monthly CIT advance payment due by the 20th (quarterly option for small taxpayers) Korduv 25. oktoober 2026 Poland JPK_V7 (VAT records and declaration) Poland: JPK_V7M monthly VAT return and payment due by the 25th Korduv 15. november 2026 Poland ZUS social insurance contributions Poland: ZUS social insurance contributions and DRA declaration due by the 15th (legal persons) Korduv 20. november 2026 Poland CIT advance payments Poland: monthly CIT advance payment due by the 20th (quarterly option for small taxpayers) Korduv 25. november 2026 Poland JPK_V7 (VAT records and declaration) Poland: JPK_V7M monthly VAT return and payment due by the 25th Korduv 15. detsember 2026 Poland ZUS social insurance contributions Poland: ZUS social insurance contributions and DRA declaration due by the 15th (legal persons) Korduv 20. detsember 2026 Poland CIT advance payments Poland: monthly CIT advance payment due by the 20th (quarterly option for small taxpayers) Korduv 25. detsember 2026 Poland JPK_V7 (VAT records and declaration) Poland: JPK_V7M monthly VAT return and payment due by the 25th Korduv 1. jaanuar 2027 Poland JPK_CIT / JPK_KR_PD (structured accounting books) Poland: JPK_CIT digital accounting-books reporting becomes mandatory for remaining CIT taxpayers 12. jaanuar 2027 Data Act Andmemäärus: pilveteenuse pakkujad ei tohi enam küsida vahetus- ja andmete väljaviimise tasusid 15. jaanuar 2027 Poland ZUS social insurance contributions Poland: ZUS social insurance contributions and DRA declaration due by the 15th (legal persons) Korduv 20. jaanuar 2027 Poland CIT advance payments Poland: monthly CIT advance payment due by the 20th (quarterly option for small taxpayers) Korduv 25. jaanuar 2027 Poland JPK_V7 (VAT records and declaration) Poland: JPK_V7M monthly VAT return and payment due by the 25th Korduv 15. veebruar 2027 Poland ZUS social insurance contributions Poland: ZUS social insurance contributions and DRA declaration due by the 15th (legal persons) Korduv 20. veebruar 2027 Poland CIT advance payments Poland: monthly CIT advance payment due by the 20th (quarterly option for small taxpayers) Korduv 25. veebruar 2027 Poland JPK_V7 (VAT records and declaration) Poland: JPK_V7M monthly VAT return and payment due by the 25th Korduv 28. veebruar 2027 Poland KOBiZE national emissions database report Poland: annual report to the national GHG/emissions database (KOBiZE) due by end of February Korduv 15. märts 2027 Poland ZUS social insurance contributions Poland: ZUS social insurance contributions and DRA declaration due by the 15th (legal persons) Korduv 20. märts 2027 Poland CIT advance payments Poland: monthly CIT advance payment due by the 20th (quarterly option for small taxpayers) Korduv 25. märts 2027 Poland JPK_V7 (VAT records and declaration) Poland: JPK_V7M monthly VAT return and payment due by the 25th Korduv 31. märts 2027 Poland CIT-8 annual return Poland: annual CIT-8 corporate income tax return due by 31 March Korduv 31. märts 2027 Poland environmental-use fee (opłata za korzystanie ze środowiska) Poland: annual environmental-use fee (opłata za korzystanie ze środowiska) due by 31 March Korduv 15. aprill 2027 Poland ZUS social insurance contributions Poland: ZUS social insurance contributions and DRA declaration due by the 15th (legal persons) Korduv 20. aprill 2027 Poland CIT advance payments Poland: monthly CIT advance payment due by the 20th (quarterly option for small taxpayers) Korduv 25. aprill 2027 Poland JPK_V7 (VAT records and declaration) Poland: JPK_V7M monthly VAT return and payment due by the 25th Korduv 15. mai 2027 Poland ZUS social insurance contributions Poland: ZUS social insurance contributions and DRA declaration due by the 15th (legal persons) Korduv 20. mai 2027 Poland CIT advance payments Poland: monthly CIT advance payment due by the 20th (quarterly option for small taxpayers) Korduv 25. mai 2027 Poland JPK_V7 (VAT records and declaration) Poland: JPK_V7M monthly VAT return and payment due by the 25th Korduv 15. juuni 2027 Poland ZUS social insurance contributions Poland: ZUS social insurance contributions and DRA declaration due by the 15th (legal persons) Korduv 20. juuni 2027 Poland CIT advance payments Poland: monthly CIT advance payment due by the 20th (quarterly option for small taxpayers) Korduv 25. juuni 2027 Poland JPK_V7 (VAT records and declaration) Poland: JPK_V7M monthly VAT return and payment due by the 25th Korduv 15. juuli 2027 Poland ZUS social insurance contributions Poland: ZUS social insurance contributions and DRA declaration due by the 15th (legal persons) Korduv 15. juuli 2027 Poland annual financial statements - KRS/RDF filing Poland: e-financial statements filing to KRS via RDF due within 15 days of approval (by 15 July for calendar-year filers) Korduv 20. juuli 2027 Poland CIT advance payments Poland: monthly CIT advance payment due by the 20th (quarterly option for small taxpayers) Korduv 25. juuli 2027 Poland JPK_V7 (VAT records and declaration) Poland: JPK_V7M monthly VAT return and payment due by the 25th Korduv 15. august 2027 Poland ZUS social insurance contributions Poland: ZUS social insurance contributions and DRA declaration due by the 15th (legal persons) Korduv 20. august 2027 Poland CIT advance payments Poland: monthly CIT advance payment due by the 20th (quarterly option for small taxpayers) Korduv 25. august 2027 Poland JPK_V7 (VAT records and declaration) Poland: JPK_V7M monthly VAT return and payment due by the 25th Korduv