Buying or verifying a property can often involve a confusing list of numbers.
A sale deed may mention a Survey Number, while the Patta shows a sub-division number. An urban property may instead have a Town Survey Number (TS No.), while a plotted development has a Plot Number and the completed building has a Door Number.
These numbers are not interchangeable.
Each one is created for a different purpose and helps identify the property at a different level. Understanding the difference can make it easier for buyers and landowners to read property documents and carry out basic due diligence.
The Simple Way to Understand Property Numbers
Property identification numbers can broadly be grouped according to their purpose:
- Land survey and revenue identification
- Revenue account and ownership-related records
- Planning and layout identification
- Local body and building identification
- Apartment-specific identification
Let us look at each group.
1. Land Survey and Revenue Identification Numbers
These numbers are primarily used to identify the actual parcel of land in government survey and revenue records.
Survey Number (S.No.)
A Survey Number, commonly written as S.No., identifies a parcel of land in survey and revenue records.
For example:
Survey No. 120
A large area of land may originally be recorded under one Survey Number.
Survey Numbers are particularly common in revenue villages and areas covered by the regular land survey system.
Where can you find the Survey Number?
A Survey Number may be found in:
- Sale Deed
- Patta
- Revenue records
- FMB Sketch
- Encumbrance Certificate
- Parent documents
- Government land records
However, buyers should not rely only on the Survey Number. It is important to check whether the land has subsequently been subdivided.
Sub-Division Number
When a larger Survey Number is divided into smaller land parcels, the government may assign sub-division numbers.
For example:
Original Survey No.: 120
After subdivision, the records may contain references such as:
- Survey No. 120/1A
- Survey No. 120/1B
- Survey No. 120/2
The sub-division reference helps identify the exact portion of the larger original Survey Number.
Why is this important?
A buyer may find that an old document refers only to Survey No. 120, while a recent Patta refers to a more specific sub-division.
Therefore, property verification may require checking whether the survey number in older title documents correctly corresponds to the current sub-division number.
Where can you find it?
- Patta
- Sale Deed
- FMB Sketch
- Revenue records
- Property title documents
RS Number (R.S. No.)
RS No. is commonly associated with a re-survey or revised survey reference used in land and revenue records. When an area is surveyed again or its survey records are reorganised, land parcels may be assigned revised or re-survey numbers.
For eample:
R.S. No. 125/3A
An RS Number should be verified with the relevant revenue records to understand its relationship with any older Survey Number.
Where can you find it?
Depending on the locality and applicable survey system, it may appear in:
- Sale Deed
- Patta
- Revenue records
- Land survey records
- Older and newer title documents
Important point for buyers
Do not assume that an RS Number and an old Survey Number automatically refer to the same land merely because they appear similar.
Where older and newer property documents contain different survey references, the correlation should be verified using the relevant official land records.
TS Number (T.S. No.) – Town Survey Number
A TS Number generally means Town Survey Number.
It is used to identify land parcels in areas covered by the town survey system, particularly urban and town areas.
For example:
TS No. 45/2
Instead of a conventional Survey Number used in a revenue village, an urban property may be identified through a Town Survey Number.
In some documents, additional references such as Ward and Block Numbers may also appear along with the TS Number.
For example:
Ward No. 10, Block No. 5, TS No. 45/2
Where can you find it?
- Sale Deed
- Town Survey records
- Patta or land records, where applicable
- Urban property documents
- Government survey records
2. Revenue Account and Land Record Identification
These numbers do not necessarily identify the physical land parcel in the same way as a Survey Number.
Instead, they are connected with revenue records and government land accounts.
Patta Number
A Patta Number identifies a Patta or revenue account record.
For example:
Patta No. 1234
A Patta may contain details such as:
- Name of the recorded pattadar
- Survey Number
- Sub-division Number
- Extent of land
- Classification of land
Where can you find the Patta Number?
- Patta document
- Government land records
- Revenue Department records
- Sometimes in the Sale Deed
3. Planning and Layout Identification Numbers
Once a large parcel of land is developed into a plotted layout, additional numbers may be created to identify individual plots and the relevant planning approval.
Plot Number
A Plot Number identifies an individual plot within a layout.
For example:
Plot No. 15
A larger Survey Number may be developed into multiple plots.
For example:
Survey No. 120
may contain:
- Plot No. 1
- Plot No. 2
- Plot No. 3
- Plot No. 15
An important difference to be noted is that Plot No. 15 alone does not uniquely identify a property because there can be many Plot No. 15s in different layouts and locations.
The complete property description should also identify details such as:
- Layout name
- Survey Number
- Village
- Taluk
- District
Where can you find it?
- Sale Deed
- Approved layout plan
- Planning approval documents
- Developer documents
Layout Approval Number
A layout may also have an approval reference or approval number issued by the competent planning authority.
This number identifies the approval granted to the layout or development, rather than replacing the Survey Number or Plot Number.
Where can you find it?
- Approved layout plan
- Planning approval documents
- Developer documents
- Property records referring to the approved layout
Why is it important?
A Plot Number may tell you which plot you are looking at.
The underlying Survey Number helps identify the original land.
The layout approval reference helps establish which planning approval applies to the layout.
These references may therefore need to be examined together during property due diligence.
4. Local Body and Building Identification Numbers
Once land is developed and a building is constructed, local bodies may use separate identification numbers for administration and taxation.
Ward Number
A Ward Number identifies the larger administrative area in which the property is located.
For example:
Ward No. 12
A Ward Number identifies the administrative division of a Corporation, Municipality or other local body.
For example, the Greater Chennai Corporation is divided into multiple administrative wards. A property may fall under Ward No. 12 of the Corporation. Ward No. 12 falls under Zone 1 – Thiruvottiyur.
Where can you find it?
- Property tax records
- Local body records
- Municipal or Corporation documents
- Certain urban land records
Ward boundaries can also change following administrative or electoral delimitation.
Block Number
A Block Number may be used as part of a larger survey or administrative identification system.
It can be particularly useful in town survey records.
For example:
Ward No. 12
Block No. 5
TS No. 45
Together, these references help locate the property within the relevant town survey system.
Where can you find it?
- Town Survey records
- Urban land records
- Sale Deeds where applicable
Door Number
A Door Number identifies a particular building or premises.
For example:
Door No. 25, Anna Street
It is mainly an address and local administration identifier.
Where can you find it?
- Property tax receipt
- Electricity connection records
- Water and sewerage records
- Local body records
- Sale Deed
Important point
A Door Number is not a substitute for a Survey Number or TS Number when verifying the underlying land.
Door Numbers can also change due to renumbering by local authorities.
Property Tax Assessment Number
Local bodies may assign a separate Property Tax Assessment Number or similar reference for tax administration.
This is primarily used for:
- Property tax assessment
- Tax payment
- Local body records
Where can you find it?
- Property tax receipts
- Corporation or Municipality records
- Local body property databases
5. Apartment and Building Identification
Apartment properties involve another set of identifiers because the buyer is purchasing a specific unit along with a share in the underlying land.
Flat Number
The Flat Number identifies the particular apartment unit.
For example:
Flat No. B-302
This identifies the apartment within the building.
It does not independently identify the underlying land parcel.
The land should still be connected to the relevant:
- Survey Number or TS Number
- Patta and land records, where applicable
- Parent documents
UDS – Undivided Share of Land
UDS means Undivided Share of Land.
This is not an identification number, but it is one of the most important property details for apartment buyers.
For example:
UDS: 500 sq. ft.
An apartment owner generally owns a specific apartment along with a proportionate undivided share in the underlying land.
Therefore, an apartment sale document may contain several different references:
- Flat Number
- Survey Number or TS Number
- Extent of total land
- UDS
Each of these identifies a different aspect of the property.
How the Numbers Work Together
A plotted property may be identified through multiple levels.
For example:
Survey No. 120/3A → Approved Layout → Plot No. 15
An urban property may be described as:
Ward No. 10 → Block No. 5 → TS No. 45/2 → Door No. 25
An apartment may involve:
Survey/TS Number → Total Land → Building → Flat Number → UDS
This is why buyers should avoid checking only one number in isolation.
The Difference
| Property Number / Reference | What It Means | What It Identifies | Main Purpose | Commonly Found In |
|---|---|---|---|---|
| Survey No. (S.No.) | Survey Number | Parcel of land | Land survey and revenue identification | Patta, Sale Deed, FMB, EC |
| Sub-division No. | Division of a Survey Number | Specific portion of original land | Identifying subdivided land | Patta, FMB, Sale Deed |
| RS No. | Re-survey/revised survey reference, depending on the applicable local survey system | Land parcel under the relevant survey system | Revenue and survey identification | Revenue records, Patta, Sale Deed |
| TS No. | Town Survey Number | Land parcel in town survey records | Urban land identification | Town Survey records, Sale Deed |
| Patta No. | Patta/revenue account reference | Revenue record/account | Land revenue records | Patta, government land records |
| Plot No. | Plot Number | Individual plot in a layout | Layout identification | Sale Deed, layout plan |
| Layout Approval No. | Planning approval reference | Approved layout/development | Planning approval | Approved layout documents |
| Ward No. | Administrative Ward Number | Larger local body area | Local administration | Property tax and local body records |
| Block No. | Survey/administrative block reference | Larger grouping within survey records | Town survey identification | Town Survey and urban land records |
| Door No. | Premises or building number | Building/address | Local administration and addressing | Tax, EB and local body records |
| Assessment No. | Property tax account reference | Tax assessment record | Property taxation | Property tax receipt |
| Flat No. | Apartment/unit number | Individual apartment | Building/unit identification | Sale Deed and apartment documents |
| UDS | Undivided Share of Land | Owner’s proportionate share in land | Apartment land ownership | Sale Deed and apartment documents |
The Most Important Difference to Remember
The easiest way to understand these numbers is to ask one question:
What exactly is this number identifying?
- Survey No. / TS No. / RS No. → Identifies the land under the applicable survey system.
- Sub-division No. → Identifies a specific portion of a larger Survey Number.
- Patta No. → Identifies the relevant revenue record or account.
- Plot No. → Identifies a plot within a particular layout.
- Layout Approval No. → Identifies the planning approval for the layout.
- Ward and Block Numbers → Help identify the larger administrative or town survey area.
- Door No. → Identifies the building or premises.
- Assessment No. → Identifies the property tax account.
- Flat No. → Identifies the apartment unit.
- UDS → Identifies the apartment owner’s proportionate share in the underlying land.
Buyers Should Check The Numbers
A property can have several numbers because the same property is recorded by different government departments and authorities for different purposes.
The key is to establish a clear connection between the different records:
Title Document → Survey/TS/RS Reference → Current Land Record → Approved Layout or Building → Physical Property
When these references do not match, the discrepancy should be examined before proceeding with a property transaction.
Understanding these numbers may seem technical, but they form an important part of basic property due diligence. Knowing what each number identifies can help buyers ask the right questions and better understand whether the documents they are examining actually relate to the property they intend to purchase.