FMB Sketch in Tamil Nadu: What It Is and How to Check It Before Buying a Plot (2026)
If you are buying a plot in or around Chennai, you will hear many document names: patta, chitta, EC, parent deed and the FMB sketch. Most buyers check the first few carefully but skip the FMB sketch, even though it is one of the simplest ways to confirm that the land you are paying for actually exists on the ground in the shape and size the seller claims. This 2026 guide explains the FMB sketch in plain English and shows you how to use it before you pay any advance.
What Is an FMB Sketch?
FMB stands for Field Measurement Book. It is a survey map maintained by the Tamil Nadu Survey and Land Records Department for each survey number in a village. The sketch shows the boundary of the survey number (or sub-division), its measurements, the neighbouring survey numbers on each side and nearby features such as roads, canals or water bodies.
In simple terms, patta tells you who owns the land, while the FMB sketch tells you where the land is and what shape and size it has on the government record.
Why Plot Buyers Should Check It
It confirms the location. The survey number written in the sale deed should match a real piece of land in the right village. The FMB sketch lets you see that survey number on a map.
It confirms the size and shape. If the seller says the plot is a regular rectangle but the FMB shows an odd shape or smaller measurements, you need answers before you go further.
It shows neighbouring land. The sketch lists the adjoining survey numbers. This helps you spot if the plot touches a lake, canal, poramboke land or a government road that may affect access or approvals.
It helps with patta transfer later. When you apply for patta in your name, the land records team relies on survey data. A plot whose details already match the FMB usually goes through more smoothly.
How to View the FMB Sketch Online
The Tamil Nadu government provides land record services online through the official e-services portal of the Revenue Department (search for "Tamil Nilam" or "eservices.tn.gov.in"). The general steps are:
1. Open the e-services land records page and choose the option to view the FMB sketch.
2. Select the district, taluk and village where the plot is located.
3. Enter the survey number and sub-division number given in the seller's documents.
4. View or download the sketch.
Not every village has every record online, and some urban survey areas follow a different format. If you cannot find the sketch online, you can request a certified copy at the taluk office or through the local surveyor. Always keep a printed or PDF copy with your property file.
How to Match the FMB With Your Other Documents
The FMB sketch is most useful when you compare it with the rest of the paperwork:
Patta and chitta: The survey number and sub-division on the patta should match the FMB. The extent (area) should also be broadly consistent.
Sale deed and parent documents: The boundaries described in the deed (north, south, east, west) should agree with the neighbours shown on the FMB.
Approved layout plan: For a DTCP or CMDA approved layout, the layout plan should sit inside the survey numbers shown on the FMB. Ask the developer which survey numbers the layout covers.
Encumbrance certificate: Search the EC using the same survey number so that you see all past transactions on that land.
Red Flags to Watch For
Be careful if you notice any of these:
- The survey number on the deed cannot be found on the FMB, or appears in a different village.
- The measurements on the FMB are clearly smaller than the extent being sold.
- The plot is shown next to a lake, canal, river bank or poramboke land, and the seller cannot explain access and approvals.
- Several sellers are selling plots from the same survey number without a clear sub-division.
- The seller avoids sharing the survey number or says the FMB is "not needed".
None of these automatically means the deal is bad, but each one needs a clear written answer, and ideally a check by your lawyer.
Get a Physical Survey Done
An online sketch is a record, not a guarantee of what is on the ground. Before registration, it is wise to hire a licensed surveyor to measure the plot and compare it with the FMB and the layout plan. The surveyor can confirm the boundary stones, road width and exact extent. This small cost can save you from a boundary dispute with neighbours years later.
Quick Checklist Before You Pay an Advance
- Get the survey number and sub-division from the seller.
- Download the FMB sketch and compare it with patta, sale deed and layout plan.
- Check the EC for the same survey number.
- Visit the site and match the shape and neighbours with the sketch.
- Get a surveyor's measurement before registration.
- Have a property lawyer review everything together.
How 4KREALTY Can Help
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