Income Tax Return 2026: Key May deadlines to avoid DIAN penalties

The income tax return 2026 has already started for several taxpayers in Colombia, especially legal entities, VAT taxpayers, withholding agents, taxpayers under the Simple Tax Regime, and individuals required to file wealth tax. In May, DIAN concentrates important deadlines between May 12 and May 26, 2026, according to the last digit of the NIT.

If you have a company, manage tax obligations, are responsible for VAT, or must declare wealth, this month is not the time to improvise.

The Colombian Tax and Customs Authority —DIAN— published the 2026 tax calendar and enabled the May deadlines so taxpayers can review their dates, prepare documents, and comply on time.

In this guide, we explain clearly and in a reader-friendly way which obligations are due in May 2026, which dates you need to keep in mind, how the calendar works according to the NIT, and what recommendations you should follow to avoid penalties, interest, or problems with the tax authority.

Why is May 2026 a key month for the income tax return and other taxes?

May 2026 is an especially important month because it concentrates high-impact tax obligations for companies, individuals with significant wealth, and taxpayers responsible for national taxes.

During this month, among other obligations, the following are due:

• The filing and payment of the first installment of the income tax for legal entities.
• The filing of the wealth tax return for obligated individuals and unsettled estates.
• The bimonthly and four-month VAT return.
• Withholding tax corresponding to April 2026.
• The bimonthly advance payment of the Simple Tax Regime.
• The annual foreign assets declaration for legal entities.
• The national consumption tax.
• Certain taxes with a single due date, such as carbon tax, gasoline, ACPM, sugary drinks, and services provided from abroad.

This means that, if you are a taxpayer, it is not enough to know that “you have to file an income tax return.” You need to identify exactly which obligation applies to you, what your deadline is, and which form or supporting document you need to prepare.

The most common mistake is leaving everything until the last day.

And when it comes to taxes, leaving things until the end can be expensive.

Income tax return 2026 for legal entities: May deadlines

One of the main obligations in May is the filing and payment of the first installment of the income tax and complementary taxes for legal entities.

According to DIAN, between May 12 and May 26, 2026, legal entities must file the return, pay the first installment, calculate the advance payment, and pay the first installment of the additional tax points, when applicable. The date depends on the last digit of the NIT, not including the verification digit.

Income tax calendar for legal entities in May 2026

This calendar seeks to distribute deadlines and prevent all taxpayers from filing on the same day.

But in practice, this also means that each company must clearly know its NIT and review its exact deadline in advance.

If your company files after the deadline, it may face penalties, late-payment interest, and possible reviews by DIAN.

Does the income tax return for individuals also start in May?

Here it is important to make a clarification.

The income tax return for individuals under the general calendar does not start in May. According to DIAN’s 2026 tax calendar, income tax deadlines for individuals begin in August and extend until October, depending on the last two digits of the NIT.

However, in May there is an important obligation for certain individuals: the wealth tax.

That is why, if you are an individual, you should not assume that May does not apply to you. If you have a high net worth, you may be required to file and pay the first installment of the wealth tax during this month.

Wealth tax 2026: who must file in May

The wealth tax applies to individuals and unsettled estates that, as of January 1, 2026, have net worth equal to or greater than 72,000 UVT.

DIAN explains that net worth corresponds to gross assets minus liabilities. For those who meet this requirement, the return and payment of the first installment must be made between May 12 and May 26, 2026, according to the last digit of the NIT.

Wealth tax deadlines in May 2026

This point is especially relevant for individuals with significant assets in Colombia or abroad.

If you own real estate, investments, bank accounts, companies, vehicles, or other relevant assets, it is advisable to review your situation in time.

It is not just about knowing how much you own. You also need to correctly calculate your liabilities, supporting documents, and asset values.

VAT in May 2026: bimonthly and four-month return

May is also a key month for taxpayers responsible for the Value Added Tax —VAT—.

DIAN establishes two main VAT deadlines in May:

• Bimonthly VAT: corresponding to the March-April 2026 period.
• Four-month VAT: corresponding to the January-April 2026 period.

In both cases, the deadlines run from May 12 to May 26, 2026, according to the last digit of the NIT.

Bimonthly VAT: March-April 2026

Taxpayers responsible for bimonthly VAT must file and pay the return corresponding to the March-April period.

This applies, for example, to taxpayers who, due to their income level or activity, must file VAT every two months.

Four-month VAT: January-April 2026

VAT taxpayers with gross income as of December 31, 2025, below 92,000 UVT must file and pay the return for the January-April 2026 four-month period. DIAN indicates that, for this calculation, the 2025 UVT value is $49,799 COP.

VAT deadlines in May 2026

If you are responsible for VAT, it is not enough to file the return. You must also verify that sales, purchases, deductible taxes, withholdings, and electronic invoicing are properly reconciled.

An error in VAT can generate differences that DIAN may later question.

Withholding tax: May 2026 deadlines

All withholding agents or self-withholding agents for income tax and complementary taxes must file the return corresponding to April 2026 and pay the withholdings or self-withholdings made.

The deadline also runs from May 12 to May 26, 2026, according to the last digit of the NIT.

This applies to companies and taxpayers that have made withholdings for concepts such as:

• Payroll payments.
• Professional fees.
• Services.
• Purchases.
• Leases.
• Commissions.
• Payments subject to self-withholding.

Withholding tax is an obligation that usually repeats every month, but that does not mean it should be handled automatically.

Before filing, it is advisable to verify that certificates, bases, rates, and amounts withheld match the accounting records and reported information.

Foreign assets declaration: legal entities

Between May 12 and May 26, 2026, legal entities that have assets abroad must file the annual foreign assets declaration. The date depends on the last digit of the NIT.

This obligation is important for Colombian companies that own:

• Bank accounts abroad.
• Investments outside Colombia.
• Shares or interests in foreign entities.
• Movable or immovable property located outside the country.
• Economic rights abroad.

One of the most frequent mistakes is believing that only assets located in Colombia must be declared.

But if the company has assets outside the country and meets the applicable criteria, it must report them correctly.

Simple Tax Regime: bimonthly advance payment in May

Taxpayers registered under the Simple Tax Regime —RST— also have deadlines in May.

According to DIAN, between May 12 and May 26, 2026, taxpayers registered under the RST must file and pay the bimonthly advance corresponding to the January-February 2026 period, using the SIMPLE electronic receipt, form 2593.

This point is key for small businesses, entrepreneurs, and businesses registered under SIMPLE.

Although the Simple Tax Regime seeks to facilitate tax compliance, that does not mean it does not have strict deadlines.

If you are under the RST, you must review:

• Income for the period.
• Registered economic activity.
• Applicable rate.
• Previous advance payments.
• Payments made.
• Information reported in electronic invoicing.

National consumption tax in May 2026

The national consumption tax is also due in May for certain taxpayers.

DIAN states that between May 12 and May 26, 2026, providers of mobile phone services, establishments that sell prepared food and beverages, sellers of goods subject to consumption tax or used vehicles, and taxpayers responsible for the consumption tax on plastic bags and cannabis must file and pay the return corresponding to the March-April bimonthly period.

This tax may apply to businesses such as restaurants, bars, food service providers, certain retailers, and specific activities.

If your business charges consumption tax, you must clearly separate this amount, report it, and pay it within the corresponding deadline.

Taxes with a single due date: May 15, 2026

Not all May obligations depend on the last digit of the NIT.

Some taxes have a single due date: May 15, 2026.

This means that all responsible taxpayers must file and pay by that day at the latest, without a staggered calendar.

Tax on sugary drinks and ultra-processed foods

Those responsible for the tax on sugary drinks and industrially ultra-processed edible products or products with high content of added sugars, sodium, or saturated fats must file and pay the March-April bimonthly period by May 15, 2026, regardless of the NIT.

National carbon tax

Those responsible for the national carbon tax must file and pay the March-April bimonthly period by May 15, 2026. This deadline applies to all NITs.

Gasoline and ACPM tax

Those responsible for the national gasoline and ACPM tax must file and pay the return corresponding to April by May 15, 2026, regardless of the NIT.

VAT for service providers from abroad

Service providers from abroad must file and pay the VAT return for the March-April bimonthly period by May 15, 2026.

Significant Economic Presence —SEP—

Non-resident individuals or entities not domiciled in Colombia with Significant Economic Presence —SEP— that choose to file and pay income tax and complementary taxes must make the bimonthly advance payment corresponding to March and April by May 15, 2026, using form 115.

This type of obligation is especially important for foreign companies or platforms that generate income from users or clients in Colombia, even without having a physical domicile in the country.

What happens if you file late or do not pay on time?

Filing late or paying after the deadline can generate financial consequences.

Among the most common are:

• Penalty for late filing.
• Late-payment interest.
• DIAN requirements.
• Possible audit processes.
• Difficulties keeping your tax status up to date.
• Risk of inconsistencies with exogenous information, electronic invoicing, or third-party reports.

In other words, not filing on time does not only mean paying a fine.

It can also open the door to deeper reviews of accounting, supporting documents, income, costs, deductions, and reported information.

That is why the best recommendation is to prepare the return before the deadline, not on the same day.

How to prepare for the income tax return 2026 and May deadlines

To comply correctly, you need more than just knowing the date.

You need to have the information ready, review your obligations, and avoid mistakes before filing.

1. Verify your NIT and the last digit

The May calendar depends on the last digit of the NIT, without taking into account the verification digit.

This detail seems simple, but it can create confusion.

Before filing, confirm your NIT in the RUT and verify which date corresponds to you.

2. Review which obligations you have active

Not all taxpayers have the same responsibilities.

You must review whether any of the following apply to you:

• Income tax for legal entities.
• Bimonthly VAT.
• Four-month VAT.
• Withholding tax.
• Simple Tax Regime.
• Wealth tax.
• Foreign assets.
• National consumption tax.
• SEP.
• Other national taxes.

The safest way to do this is to review the RUT, the economic activity, the registered responsibilities, and the reality of your operations.

3. Organize your accounting information

Before filing, make sure the following information is reconciled:

• Income.
• Costs.
• Deductions.
• Expenses.
• Withholdings made.
• Withholdings made to you.
• VAT generated.
• Deductible VAT.
• Electronic invoicing.
• Electronic payroll.
• Bank statements.
• Accounts receivable and payable.
• Assets and liabilities.

A well-prepared tax return starts with organized accounting.

4. Review exogenous information and third-party reports

DIAN constantly cross-checks information.

That is why, if your returns do not match what is reported by banks, clients, suppliers, employers, or third parties, you may receive requirements.

Before filing, it is advisable to review possible differences and prepare supporting documents.

5. Do not wait until the last day

Systems may fail, passwords may be expired, the electronic signature may need updating, or an inconsistency may appear at the last minute.

If you wait until the deadline day, any small problem can turn into a penalty.

Ideally, you should review everything several days in advance.

Frequent mistakes when filing in May 2026

Confusing the legal entity deadline with the individual deadline

The income tax return for legal entities is due in May, but the income tax return for individuals under the general calendar begins in August. Confusing these calendars can lead to planning mistakes.

Not checking whether wealth tax applies

Some individuals believe they have no obligations in May because their income tax return is due later.

But if they meet the net worth threshold, they may have a wealth tax obligation in May.

Filing VAT without reconciling electronic invoicing

VAT must be aligned with invoicing, purchases, deductible taxes, and accounting.

Filing with quick or incomplete figures can generate differences.

Forgetting withholding tax

Withholding tax is monthly and must be filed even when the taxpayer is focused on other obligations.

Not updating the RUT

If the RUT does not correctly reflect your economic activity or tax responsibilities, you may have problems filing or complying correctly.

Final recommendations to avoid DIAN penalties

If you have deadlines in May 2026, this is the time to act.

Do not wait until the exact date assigned to your NIT arrives.

Start by reviewing your obligations, organizing documents, validating your figures, and confirming that you have access to DIAN’s digital services.

It is also advisable to have accounting or tax support if you have several responsibilities, assets abroad, international operations, significant wealth, or a company with relevant financial activity.

At Nexo Legal, we help companies, foreigners, investors, and taxpayers in Colombia review their tax obligations, prepare their returns, and comply correctly before DIAN.

Complying on time does not only avoid fines.

It also gives you peace of mind, financial order, and security in case of future reviews.

Conclusion: the income tax return 2026 and May deadlines should not be left until the end

The income tax return 2026 and the other May tax deadlines are already underway.

Between May 12 and May 26, many companies and taxpayers must comply with key obligations before DIAN. In addition, some taxes have a single due date on May 15, without depending on the NIT.

The best decision is to prepare in advance.

Review your calendar, confirm your obligations, organize your documents, and file everything within the deadline.

Because when it comes to taxes, doing things correctly from the beginning is always easier than correcting them later.

FAQs about income tax return 2026 and DIAN’s May calendar

When does the 2026 income tax return for legal entities begin?

The income tax return for legal entities in May 2026 is due between May 12 and May 26, according to the last digit of the NIT.

Is the income tax return for individuals due in May 2026?

Not under the general calendar. The income tax return for individuals begins in August 2026. However, some individuals may be required to file and pay wealth tax in May if they meet the established threshold.

Which taxes are due in May 2026?

In May, obligations such as income tax for legal entities, wealth tax, bimonthly VAT, four-month VAT, withholding tax, foreign assets, national consumption tax, and the bimonthly advance payment of the Simple Tax Regime are due.

Which taxes have a single due date on May 15, 2026?

The taxes with a single due date include the tax on sugary drinks and ultra-processed foods, national carbon tax, gasoline and ACPM tax, VAT for services provided from abroad, and advance payments for Significant Economic Presence.

How do I know which date corresponds to me for filing?

You must review the last digit of your NIT, without taking into account the verification digit. Based on that number, DIAN assigns a date between May 12 and May 26, 2026, for many obligations.

What happens if I file late before DIAN?

You may face financial penalties, late-payment interest, requirements, and possible audit processes. That is why it is important to file and pay within the corresponding deadline.

What should I prepare before filing?

You should organize your accounting, electronic invoicing, income supports, costs, deductions, withholdings, VAT, bank statements, assets, liabilities, and any information required according to your tax obligation.