New York City acknowledged errors in its pied-à-terre tax outreach, citing mistaken notices to more than 1,200 property owners and an extended deadline for residency documentation. The pied-à-terre tax targets high-value second homes, and officials say requiring proof of residency is an intentional design of the law, not an illegal process. The Department of Finance notes some letters were issued when records did not confirm a primary residence. Nearly 3,000 appeals have been approved, with more than 2,600 under review. New notices will be mailed to 10,800 owners by August 31 using 2025 state tax data. The proof-of-residency deadline is October 6.