Tax Return Filing in Iceland
Reviewed by the Commoner Law Editorial Team. Sourced from Icelandic Acts of the Althingi, statutory instruments, and official guidance. Written in plain language for general understanding — this is educational content, not legal advice. Our editorial standards
What is this right?
All taxpayers in Iceland must file an annual tax return:
- Filing deadline: 13 March 2026 for income year 2025 (individuals filing electronically; Skatturinn does not grant extensions to individuals). Accountants/auditors filing on a client's behalf have until 15 April 2026.
- Pre-filled returns: RSK provides a pre-drafted return with salary, real estate, vehicles, bank accounts, and debt data pre-populated. You confirm or correct it.
- Late filing penalty: A surcharge of up to 25% on estimated additional tax when no return is filed.
- Assessment timeline: Final assessments are generally completed by May 31 of the assessment year.
- Payment of balance: Additional tax owed is divided into 7 due dates. Overpayments are refunded.
- Right to amend: You can file amended returns to correct errors or omissions.
When does it apply?
- You are domiciled in Iceland and received taxable income during the previous year.
- Even if your return is pre-filled, you are responsible for its accuracy.
What to Do If You Missed the Tax Return Deadline or Made an Error on Your Return in Iceland
- Log in to skattur.is using rafrænt skilríki (electronic ID via mobile certificate or e-ID card) or Íslykill (web key issued by Þjóðskrá).
- Review the pre-filled return carefully — check the salary, real estate, vehicle, bank account, and debt entries Skatturinn has imported. Look for missing income, incorrect deductions, or outdated information.
- Add deductions and adjust — interest expense (vaxtagjöld) for housing, mortgage, donations, professional fees, foreign income, and any items not auto-populated.
- Submit by 13 March 2026 for income year 2025 (Skatturinn does not grant extensions to individuals). Accountants/auditors filing on a client's behalf have until 15 April 2026. If you discover an error after filing, submit an amended return as soon as possible.
What should you NOT do?
- Don't miss the March deadline — the 25% surcharge on estimated tax is significant.
- Don't assume the pre-filled return is always correct — you are legally responsible for its accuracy.
- Don't discard records — retain all supporting documents for at least 6 years.
Common Questions
When is the Icelandic tax return deadline?
13 March 2026 for income year 2025 (individuals filing electronically). Skatturinn does not grant extensions to individuals. Accountants and auditors filing on behalf of clients have until 15 April 2026. Final tax assessments are generally completed by 31 May of the assessment year. Additional tax owed is divided into 7 due dates, while overpayments are refunded.
Do I have to fill out the Icelandic tax return from scratch?
No. RSK provides a pre-drafted return with salary, real estate, vehicles, bank accounts, and debt data pre-populated. You confirm or correct it through the Skatturinn (RSK) portal. Even though it is pre-filled, you are legally responsible for its accuracy — review carefully for missing income, incorrect deductions, or outdated information.
What is the penalty for filing a late tax return in Iceland?
A surcharge of up to 25% on estimated additional tax applies when no return is filed on time. You can file an amended return to correct errors or omissions after submission. Retain all supporting documents for at least 6 years. File electronically through the Skatturinn portal as soon as possible if you miss the March deadline.
When does it apply — tax return filing?
You are domiciled in Iceland and received taxable income during the previous year.Even if your return is pre-filled, you are responsible for its accuracy.
What should I do if I missed the Icelandic tax return deadline or need to correct an error in my submitted return?
Log in to skattur.is using rafrænt skilríki (electronic ID via mobile certificate or e-ID card) or Íslykill (web key issued by Þjóðskrá).Review the pre-filled return carefully — check the salary, real estate, vehicle, bank account, and debt entries Skatturinn has imported. Look for missing income, incorrect deductions, or outdated information.Add deductions and adjust — interest expense (vaxtagjöld) for housing, mortgage, donations, professional fees, foreign income, and any items not auto-populated.Submit by 13 March 2026 for income year 2025 (Skatturinn does not grant extensions to individua...
What should you NOT do — tax return filing?
Don't miss the March deadline — the 25% surcharge on estimated tax is significant.Don't assume the pre-filled return is always correct — you are legally responsible for its accuracy.Don't discard records — retain all supporting documents for at least 6 years.