The October compliance picture
The Colombian tax authority’s October 2026 calendar identifies several obligations with different taxpayer populations and filing periods. Individual income-tax deadlines for tax year 2025 run through October, with the final dates generally assigned according to the taxpayer’s NIT. The official guidance also identifies special treatment for taxpayers domiciled in specified municipalities and administrative regions affected by the relevant emergency measures.
The calendar separately addresses withholding-at-source filings for September 2026, the national gasoline and ACPM tax for September, and other recurring obligations. Because these filings concern different periods, taxpayers should not treat “October filing” as a single event.
Individual income tax
Individuals should first determine whether they crossed any of the statutory declaration thresholds. The October guidance identifies, among other criteria, gross income of at least 1,400 UVT, assets above 4,500 UVT, or financial transactions, purchases, consumption, or credit-card use above the applicable threshold. Individuals responsible for VAT at December 31, 2025 may also have a filing obligation.
A taxpayer should then verify the exact deadline using the relevant NIT digits. The calendar states that ordinary individual deadlines extend from August through October, with the October dates covering the later NIT groups. Taxpayers in specified affected municipalities may be subject to a separate schedule.
Withholding and fuel tax
Withholding agents and self-withholders must file and pay the return for September 2026 between October 9 and October 23, 2026, according to the last NIT digit. The national gasoline and ACPM tax return for September is due by October 15, 2026, independently of the NIT-based schedule described for withholding.
These distinctions matter for companies with several tax roles. A company may be both a withholding agent and responsible for the fuel tax, creating separate returns, payment instructions, reconciliations, and approval workflows.
Practical control checklist
- Map every obligation to its tax period, not just its calendar month.
- Record the NIT digits used for each return and confirm whether the verification digit is excluded.
- Reconcile withholding ledgers to payroll, accounts payable, and accounting records.
- For individuals, preserve evidence supporting income, assets, bank movements, and VAT status.
- Confirm whether an emergency-related domicile rule changes the ordinary deadline.
- Schedule internal review at least three business days before the official due date.
Example
A Colombian company that withheld income tax during September must file in October according to its NIT. If it also operates vehicles or fuel-related activities that make it responsible for the gasoline and ACPM tax, it should create a separate October 15 control rather than assuming the withholding deadline covers both obligations.
The key planning lesson is simple: build a taxpayer-specific calendar from the official schedule, then cross-check each return against the underlying period and legal capacity.