Yes, there's a real deadline worth knowing about. The SEAI solar PV grant is a flat €1,800 through 2026, but it steps down to €1,500 from 1 January 2027 — a €300 reduction. So if you're already planning to install and you're close to the turn of the year, getting the work completed (and the grant secured) in 2026 is worth €300 more in your pocket than waiting into 2027. It's not a reason to rush a half-baked decision, but it is a reason not to dawdle if you're otherwise ready.
A couple of things to keep in mind around timing. The grant is tied to the process being done properly — an SEAI-registered installer, the application in, and a post-works BER — so "completed in 2026" means the job and paperwork actually landing before the cut, not just signing a contract. Given installers get busy and weather (especially storms) can push installs back, build in some buffer rather than aiming for late December and hoping. If your install is going to slip into 2027 regardless, it's not a disaster — €1,500 is still a meaningful grant — but plan with the real figure, not the higher one.
Also remember the grant is separate from, and stacks with, the 0% VAT on domestic solar PV, and that batteries bought as part of the install get that 0% VAT even though the grant itself doesn't fund them. So the total saving combines the grant and the VAT relief. Bottom line: budget on €1,800 for a 2026 completion and €1,500 from 2027, and if you're ready to go, the end-of-2026 deadline is a modest but real incentive to get it done.