New Survey Number to Old Survey Number API, Tamil Nadu

Example

Request

curl -X POST https://verified.realestate/api/v1/tools/current_survey_to_old \
  -H "Authorization: Bearer $LANDLENS_KEY" \
  -H "Content-Type: application/json" \
  -d '{"district_code":"35","taluk_code":"13","town_code":"005","ward_code":"001","block_code":"0011","survey_no":"66","subdiv_no":"1"}'

Responsereal answer

{
  "ok": true,
  "status": "ok",
  "data": {
    "found": true,
    "count": 1,
    "truncated": false,
    "distinct_blocks": 1,
    "ambiguous": false,
    "parcels": [
      {
        "parcel": "Pallavaram, Pallavaram: ward 001 block 0011, TS 66/1",
        "district": "Chengalpattu",
        "taluk": "Pallavaram",
        "town": "Pallavaram",
        "ward_code": "001",
        "block_code": "0011",
        "survey_no": "66",
        "subdiv_no": "1",
        "old_survey_number": "59/10PT,56/1PT,59/1PT",
        "old_survey_numbers": [
          {
            "as_printed": "59/10PT",
            "searchable": "59/10"
          },
          {
            "as_printed": "56/1PT",
            "searchable": "56/1"
          },
          {
            "as_printed": "59/1PT",
            "searchable": "59/1"
          }
        ],
        "extent": {
          "hectares": 0,
          "ares": 1,
          "square_metres_part": 37,
          "square_metres": 137,
          "square_feet": 1474.65
        },
        "street": "முத்துசாமி தெரு",
        "door_number": null,
        "land_type": "புஞ்சை"
      }
    ],
    "source": "Town survey land register (TSLR), old survey number field"
  },
  "credits_charged": 0
}

A real answer from the API (22 Oct 2026). The owner fields (a private holder's name in Tamil and English) are left out here.

What it returns

One call, the matching parcels. Without a sub-division every sub-division of the T.S. number comes back. found is false (status not_found) when the parcel is not in the register.

Field	What it holds
`parcels[].old_survey_number`	The old number field as the register prints it, e.g. 59/10PT,56/1PT,59/1PT.
`parcels[].old_survey_numbers[]`	The same, split into individual numbers: as_printed and searchable (PT and R.S. removed).
`parcels[].parcel, ward_code, block_code, survey_no, subdiv_no`	The current parcel and where it is.
`parcels[].owner, owner_english`	The holder the register records, in Tamil and in English, or null for government land.
`parcels[].extent`	The extent in hectares, ares and square metres, with square feet.
`parcels[].street, door_number, land_type`	The street and door number where recorded, and the land type.
`distinct_blocks, ambiguous`	How many blocks the matches sit in. ambiguous is true when more than one: a town survey number is unique only within its block, so send ward_code and block_code.
`count, truncated`	How many parcels came back; truncated when more than 60 matched.
`needs, towns[]`	When town_name matches several places, or none: the places to choose from.

Inputs

The JSON body of the POST is the arguments. survey_no is required. For town land send at least the district, taluk and town codes, or a town_name; add the ward and block to pin one parcel.

Argument	Type	What to send
`district_code`	string	Revenue district code
`taluk_code`	string	Revenue taluk code
`town_code`	string	Town code
`ward_code`	string	Ward code, e.g. 001
`block_code`	string	Block code, e.g. 0011
`survey_no`required	string	The current T.S. number, e.g. 66.
`subdiv_no`	string	The sub-division, e.g. 1. Leave it out for every sub-division of the number.
`village_code`	string	Revenue village code, for village (rural) land
`register`	string	"rural" or "urban", when the place code alone does not say which register is meant.
`town_name`	string	Town or village name, for example Pallavaram or a revenue village. Resolved across both registers.

Code

Set LANDLENS_KEY to your key. In an AI app, connect https://verified.realestate/mcp once and ask in plain words instead. In Postman, download this API's collection, import it (File, Import) and set apiKey.

curl -X POST https://verified.realestate/api/v1/tools/current_survey_to_old \
  -H "Authorization: Bearer $LANDLENS_KEY" \
  -H "Content-Type: application/json" \
  -d '{"district_code":"35","taluk_code":"13","town_code":"005","ward_code":"001","block_code":"0011","survey_no":"66","subdiv_no":"1"}'

import os, requests

r = requests.post(
    "https://verified.realestate/api/v1/tools/current_survey_to_old",
    headers={"Authorization": f"Bearer {os.environ['LANDLENS_KEY']}"},
    json={
        "district_code": "35",
        "taluk_code": "13",
        "town_code": "005",
        "ward_code": "001",
        "block_code": "0011",
        "survey_no": "66",
        "subdiv_no": "1"
    },
    timeout=30,
)
body = r.json()
print(body["status"], body["credits_charged"], body["data"])

const res = await fetch("https://verified.realestate/api/v1/tools/current_survey_to_old", {
  method: "POST",
  headers: {
    Authorization: `Bearer ${process.env.LANDLENS_KEY}`,
    "Content-Type": "application/json",
  },
  body: JSON.stringify({
    "district_code": "35",
    "taluk_code": "13",
    "town_code": "005",
    "ward_code": "001",
    "block_code": "0011",
    "survey_no": "66",
    "subdiv_no": "1"
  }),
});
const body = await res.json();
console.log(body.status, body.credits_charged, body.data);

The TSLR for my plot in Pallavaram says ward 001, block 0011, T.S. 66/1. What was its old survey number? I need it for an EC search.

Your AI reads the old numbers from the register and gives you each one to search. It is free.

Responses

Every answer has the same envelope. What status can say for this call:

status	What it means
`ok`	The parcel was found. Check ambiguous before relying on one parcel.
`not_found`	No parcel with that number in the register, too few codes were sent, or the town name matched several places or none.
`invalid_args`	survey_no is missing.
`free_limit_reached`	The account has used its free calls for the hour or the day. retry_after says how many seconds to wait; paid calls keep working.

Where the data comes from

Register

The town survey land register (TSLR) of Tamil Nadu, whose entry for each parcel records the old survey number the land carried before the town survey, and for village land the revenue A-register's old survey number field.

Coverage

Every parcel in the towns and villages we hold the register for. Where the register leaves the old number blank, the answer says so; the survey department's correlation statement may still have it.

How current

Read from our copy of the registers, refreshed from the revenue department's registers.

How we read it

The parcel is read by its codes. The old number field, which often holds several numbers with PT (part) marks, is returned as printed and also split into individual numbers in the form a search expects.

Who uses it

EC searches

Encumbrance records before the resurvey are indexed by the old number. Get it from the current T.S. number, then search both.

Advocates

Link a parent deed that names the old survey number to the parcel in today's patta.

Lenders

Check that the old survey number in the title documents is really the predecessor of the parcel being mortgaged.

Limits and good practice

Where the register's old number field is blank, nothing can be read from it. Try correlation_statement for the town.
Read the old number as printed alongside the split numbers. A field like 59/1,2,3 can mean 59/1, 59/2 and 59/3, and the split form may show only 2 and 3.
A T.S. number repeats across blocks. Without ward_code and block_code, check distinct_blocks.
The owner is the register's holder, not proof of title.

Pricing

Free

The new to old survey number lookup costs nothing. Free calls have their own allowance per hour and per day. Credits come from the same LandLens wallet as the chat and the minis. How billing works.

Calling at volume?

Free calls have an hourly and daily allowance. For more than that, or a platform built on these registers, we set up limits and a plan to match.

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