The AEAT has published the 2026 taxpayer calendar, highlighting that several declarations and self‑assessments have filing deadlines that conclude in July 2026. This includes model 184 for the quarterly payment of VAT, model 303 for the quarterly summary of VAT collections, and model 390 for the annual summary of VAT settlements. Additionally, the calendar specifies deadlines for model 202 for the quarterly advance corporate tax payments and model 206 for the quarterly withholding tax on income from movable capital. Taxpayers must ensure that their electronic filings are submitted before the respective deadlines to avoid penalties and interest charges. The AEAT also reminds taxpayers that late submissions may trigger automatic sanctions, and that extensions are only granted under exceptional circumstances. To facilitate compliance, the agency provides online tools, instructional guides, and a dedicated call centre for assistance. Taxpayers are encouraged to verify their filing status, update any required personal or fiscal data, and retain supporting documentation for at least four years. The calendar further indicates that certain provisional declarations may be submitted electronically through the Agency’s portal, streamlining the process and reducing the need for physical paperwork.