Most important tax obligations for April 2026

April kicks off, bringing one of the busiest tax months of the year. To help you keep everything under control and avoid mistakes or penalties, at Adlanter we have prepared a clear and practical summary of all the tax obligations you must file in April 2026, whether you are a freelancer or a company.

Our goal: give you the essentials at a glance, without getting lost among forms, deadlines, and regulations.

From April 8 to June 30

Income and Wealth Tax

• Start of online filing for Income Tax 2025 and Wealth Tax 2025.
• If the result is to be paid by direct debit, the deadline is extended until June 25.

Until April 13

INTRASTAT – Intra-Community Trade Statistics

• Submission corresponding to March 2026 for those required to provide statistical information.

Until April 20

Income and Corporate Tax – Withholdings and Advance Payments

Forms according to type of obligation:

• Large companies – March 2026: 111, 115, 117, 123, 124, 126, 128, 216, 230
• First quarter 2026: 111, 115, 117, 123, 124, 126, 128, 136, 210, 216

Income Tax – Installment Payments, First Quarter 2026

• Direct estimation: Form 130
• Objective estimation: Form 131

Corporate Tax – Installment Payments, Current Year

• General regime: Form 202
• Fiscal groups (consolidated tax): Form 222

VAT

• Recapitulative declaration of intra-Community operations – March: Form 349
• First quarter self-assessment: Form 303
• Non-periodic declaration/settlement: Form 309
• First quarter recap: Form 349
• Operations assimilated to imports: Form 380
• Refund requests (Form 308):
  • Travelers (equivalence surcharge)
  • Simplified scheme for transport
• Special regime for agriculture, livestock, and fishing: Form 341

Environmental Taxes

• Non-reusable plastic – March: Form 592
• Fluorinated gases – First quarter: Form 587 + request A23
• Non-reusable plastic – First quarter: Form 592 + request A22
• Gas, oil, and condensates extraction value 2025: Form 589
• Nuclear fuel storage 2026 – first payment: Form 585

Financial Transactions Tax

• March 2026: Form 604

Until April 30

VAT – Monthly settlements and groups

• March self-assessment: Form 303
• Group of entities: individual Form 322 / consolidated Form 353
• One-stop-shop – Imports March: Form 369
• Operations assimilated to imports: Form 380

First Quarter 2026 – One-Stop-Shop (EU and Non-EU)

• Form 369

Tax Identification Number

• Accounts without NIF reported by credit institutions: Form 195

Digital Services Tax

• First quarter: Form 490

Environmental Taxes

• Non-reusable plastic – March: accounting + registry book
• Non-reusable plastic – First quarter: accounting + registry book
• Deposit and incineration of waste – First quarter: Form 593

Informative Declarations

• Card and mobile payment operations – March: Form 170
• Update of marketable cross-border mechanisms: Form 235
• Special Canary Zone trade without transit: Form 281
• Cross-border payments (DAC7): Form 379

From April 30 to June 30

Supplementary Tax

• Communication of constitutive entity reporting: Form 240
• Informative declaration: Form 241 (For periods ending before March 31, 2025)

Want to make sure your company meets all obligations without hassle?

April is one of the busiest tax months, and we know that managing forms, deadlines, and regulations can cause stress and take up time. At Adlanter, we help you manage all your tax and accounting obligations with rigor, peace of mind, and clear guidance.

If you want to delegate this management and ensure everything is up to date, we’re here to help.