# Tax administration updates in Spain and Argentina > Live situation record from CLSTR: https://clstr.news/situations/tax-administration-updates-in-spain-and-argentina > Updated: 2026-08-22T09:31:32.000Z. Sources: 19. Developments: 4. In late July, Argentina’s tax authority extended payment deadlines for foreign‑source income taxes, allowing taxpayers to settle retained taxes until October 2026 and offering a simplified fixed‑payment option. The same announcement warned that Spanish individuals who fail to declare a second‑home property could face surcharges and heavy penalties. Two days later, Spain introduced a voluntary 30‑day “courtesy period” during which electronic tax notifications are suspended, aimed at self‑employed workers and others seeking a holiday break. The scheme does not extend existing tax deadlines. On 2 August, the Spanish Tax Agency provided further detail on the programme, describing it as a “days of courtesy” scheme that lets taxpayers suspend new electronic notices for up to 30 calendar days per year. Requests must be submitted at least seven days in advance via the agency’s portal using a digital certificate, Cl@ve, or DNI electrónico. The suspension does not halt ongoing procedures but prevents new notices from being deposited, helping users avoid fines for missed deadlines. The agency also reiterated the penalties for undeclared second residences: a self‑reported omission triggers a 1% fixed surcharge plus 1% per month of delay (capped at 15%), while discoveries by the agency can lead to interest and sanctions ranging from 50% to 150% of the unpaid tax, based on cross‑checks with cadastral and rental‑platform data. Recent guidance from the Spanish Tax Agency clarifies that taxpayers facing tax debts may request deferral or installment plans, which can allow for up to 24 monthly payments of 50 euros each. Regarding second homes, any income from short-term or seasonal rentals must be declared as real estate capital income. The agency uses data from the Cadastre and digital platforms (under the EU DAC7 directive) to detect undeclared rental income or taxable imputations on non-rented properties. ## Timeline ### 2026-08-22: Spanish Tax Agency to issue mass notifications to taxpayers in September The Spanish Tax Agency is issuing mass notifications to taxpayers, especially the self-employed, regarding discrepancies in income tax returns. Failure to address these may result in significant fines. 4 sources. https://clstr.news/cluster/spanish-tax-agency-to-issue-mass-notifications-to-taxpayers-in-september ### 2026-08-09: Spanish Tax Agency guidelines for debt deferral and rental income Spain's Tax Agency allows taxpayers to defer debts in up to 24 installments and requires the declaration of all second-home rental income, with automated monitoring via digital platforms. 4 sources. https://clstr.news/cluster/spanish-tax-agency-guidelines-for-debt-deferral-and-rental-income ### 2026-08-02: Spain's Tax Agency Offers ‘Courtesy Days’ for Vacationers Spain’s Tax Agency lets taxpayers pause electronic notices for up to 30 days a year and warns that undeclared vacation homes can incur penalties up to 150 % of owed tax. 10 sources. https://clstr.news/cluster/spains-tax-agency-offers-30day-courtesy-period-for-vacation ### 2026-07-31: Argentina Extends Foreign Income Tax Deadlines to 2026, Spain Warns of Penalties for Undeclared Vacation Homes Argentina extends foreign‑income tax deadlines to Oct 2026 and offers a fixed‑rate option; Spain warns of up to 150% penalties for not declaring vacation homes on the 2025 tax return. 2 sources. https://clstr.news/cluster/argentina-extends-foreign-income-tax-deadlines-to-2026-spain-warns-of-penalties-for-undeclared-vacat --- Cite as: Tax administration updates in Spain and Argentina. CLSTR, https://clstr.news/situations/tax-administration-updates-in-spain-and-argentina