Greece's tax authority has deployed a web-scraping algorithm that continuously monitors real estate listing portals and cross-references asking rents against official tax declarations, targeting a scheme in which landlords declare nominal rents as low as €100 while collecting actual market rates in untaxed cash — a gap authorities estimate costs the state €1.35 billion annually.
The scale of the discrepancy is stark.
The nationwide average declared monthly rent stands at €255, according to official records. Property listing platforms Spitogatos and Indomio show that actual market rents have risen 46 percent nationally since 2019, with Thessaloniki up 93 percent and Attica up 50.5 percent.
A standard 120-square-meter apartment in central Athens now lists for upwards of €1,000 per month.
AADE Governor Georgios Pitsilis said landlords flagged by the algorithm for unjustified discrepancies between listed prices and declared income will face audits of their bank deposits, personal assets and digital spending patterns by specialist financial units. Mr. Pitsilis is overseeing the enforcement drive alongside the rollout of the Property Ownership and Management Registry, a new platform that creates a permanent digital record for each property by linking cadastre data with tax profiles.
Officials acknowledge the registry cannot track physical cash payments directly — making the web-scraping and banking audit combination Greece's primary tool against cash-based rental fraud.
The enforcement push runs in parallel with the government's €500 million Anakainizo grant program, also launched this week, which aims to bring vacant apartments back onto the long-term rental market to ease the country's housing shortage.