Based on Clause 3, Article 14 of Circular 40/2021/TT-BTC, it is stipulated as follows:
Article 14. Tax management for individuals leasing assets who directly declare taxes with tax authorities
[...]
3. Deadline for submitting tax returns
The deadline for submitting tax declaration dossiers for individuals leasing assets to directly declare taxes with tax authorities is specified in point a, clause 2 and clause 3, Article 44 of the Law on Tax Administration, specifically as follows:
a) The deadline for submitting tax declaration dossiers for individuals declaring taxes for each time a payment period arises is no later than the 10th day from the date of commencement of the lease term of the payment period.
b) The deadline for submitting tax declaration dossiers for individuals who declare taxes once a year is the last day of the first month of the following calendar year.
4. Tax payment deadline
The tax payment deadline for individuals leasing assets who directly declare taxes to the tax authority is implemented according to the provisions of Clause 1, Article 55 of the Law on Tax Administration, specifically: The tax payment deadline is no later than the last day of the deadline for submitting tax declaration dossiers. In case of supplementary tax declaration dossiers, the tax payment deadline is the deadline for submitting tax declaration dossiers of the tax calculation period with errors or omissions.
According to Article 86 Circular 80/2021/TT-BTC, it is stipulated as follows:
Article 86. Deadline for submitting tax declaration dossiers and tax payment deadline
The deadline for submitting tax declaration dossiers is implemented according to the provisions of Clauses 1, 2, 3, 4, 5, Article 44 of the Law on Tax Administration and Article 10 of Decree No. 126/2020/ND-CP. The tax payment deadline is implemented according to the provisions of Clauses 1, 2, 3, Article 55 of the Law on Tax Administration and Article 18 of Decree No. 126/2020/ND-CP. In case the deadline for submitting tax declaration dossiers, the tax payment deadline coincides with the prescribed holiday, the deadline for submitting tax declaration dossiers, the tax payment deadline is calculated as the next working day of that holiday according to the provisions of the Civil Code.
Thus, the deadline for submitting tax returns for the fourth quarter of 2025 is January 31, 2026, which is Saturday, so the tax declaration for property lease according to 2026 is calculated as the next working day of the holiday, which is February 2, 2026.