What it is
The A-register is the comprehensive, permanent land record for a revenue village, maintained by the Village Administrative Officer and taluk office. It lists every survey number and sub-division with its classification — nanjai, punjai, natham, poramboke and so on — its recorded extent, and its land revenue assessment. Patta and chitta are, in effect, extracts drawn from this base register, which is why officials treat the A-register as the more authoritative source whenever the extracts disagree.
Why it matters when you buy
Most of the time you'll never need to look past the patta-chitta and FMB sketch. But if the extent or classification on those documents looks inconsistent, or a dispute arises over what the revenue department actually has on file, the A-register is what a tahsildar, surveyor, or court will refer back to. Knowing it exists — and that it sits above patta and chitta in authority — helps you understand why an official might ask for time to check the base record rather than answer from the extract alone.
Where you find it
An A-register extract for a survey number can be fetched through eservices.tn.gov.in, Tamil Nadu's e-services portal, the same source that serves patta-chitta records. The base register itself is maintained at the village and taluk revenue office, which is where you go for a certified copy or a clarification when the extract raises a question the record alone cannot settle.
What it does not prove
An A-Register extract is an administrative revenue record. It does not by itself establish legal title, possession, exact physical boundaries or planning permission.