Property tax in Kolkata: how KMC calculates your bill and how to pay it

Most flat owners in Kolkata pay their property tax without ever checking how the number was reached. That is fine until the bill doubles after a reassessment, or until you try to sell and the buyer's lawyer finds three years of dues sitting on the flat.

Here is how property tax in Kolkata actually works, what you should be paying for a normal flat, and what to check before you buy one.

How property tax in Kolkata is calculated now

The Kolkata Municipal Corporation moved from the old annual rateable value system to the Unit Area Assessment (UAA) system. Under the old method, tax depended on the rent your flat could fetch, which led to endless disputes. Under UAA, the bill depends on four things you can actually check: where the building sits, how big your space is, what it is used for, and who occupies it.

The basic formula is simple:

Annual value = Base Unit Area Value (BUAV) per sq ft x covered space x multiplicative factors. Your tax is a percentage of that annual value.

KMC has split the city into seven categories, A to G, by block. Each category has its own BUAV per sq ft: about ₹74 for A, ₹56 for B, ₹42 for C, ₹32 for D, ₹24 for E, ₹18 for F and ₹13 for G. Park Street and Ballygunge sit near the top. Outer wards added later sit near the bottom. Your category is set by the block your building is in, not by what the developer calls the project.

The five factors that change your KMC property tax

The BUAV is then adjusted by multiplicative factors (MF). These are where most bills go wrong, so read your assessment carefully.

• Location (road width): 0.6 for roads up to 2.5 m, 0.8 for 2.5 to 3.5 m, 1.0 for 3.5 to 12 m and 1.2 for roads wider than 12 m.
• Usage: residential is 1. Offices, banks and shops carry much higher factors, which is why a flat used as an office costs far more.
• Occupancy: owner-occupied is 1. A residential flat let out to a tenant is 1.5, so a let flat pays half as much again.
• Age: 1 for buildings up to 20 years old, 0.9 for 20 to 50 years and 0.8 beyond that.
• Structure: pucca is 1, semi-pucca 0.6, kuchcha 0.5. A covered car parking space carries its own factor.

If you let your flat and never told KMC, the occupancy factor is the one that will catch up with you later.

A worked example for a 1,000 sq ft flat

Take a 1,000 sq ft owner-occupied flat in a category C block, on a 6 m road, in a building under 20 years old.

Annual value = ₹42 x 1,000 x 1 x 1 x 1 x 1 x 1 = ₹42,000.

At the 20% rate that applies to most properties, the yearly tax comes to about ₹8,400. KMC applied a five-yearly 10% increase from April 2025, which takes this to roughly ₹9,200 a year, before any Howrah Bridge tax that applies in some wards.

Now change one thing: let the same flat to a tenant. The occupancy factor goes to 1.5 and the bill goes up by half. Change another: move it to a category A block and the BUAV goes from ₹42 to ₹74. That is the whole logic of property tax in Kolkata in two lines.

The rate is not flat for everyone. Properties with a low annual value pay a lower percentage, and bustee and some government properties have their own rates, from 6% upwards.

How to pay property tax in Kolkata online

You need your assessee number. It is on every bill. If you bought a new flat and have no assessee number of your own yet, see the next section first.

1. Go to the KMC website and open Online Payment, then Property Tax.
2. Choose to pay all bills, and enter your assessee number, phone number and email.
3. Check the outstanding amount. Look for old periods you did not know about.
4. Pay by card or net banking and save the e-receipt as a PDF.

KMC gives a rebate for paying the periodic demand bill on time, and a small extra rebate for paying online. Penalties and interest pile up on late bills, and KMC has run waiver schemes for old dues more than once. Do not wait for one.

Keep every receipt. When you sell, the buyer's lawyer will ask for the latest paid bill, and the bank will ask for it on any loan against the flat.

New flat? Get your own assessment done

This is the step most first-time buyers in Kolkata miss. When a new building is completed, KMC first assesses it as one premises, usually in the developer's name. Each owner then has to apply for mutation and a separate assessment of their own flat after the sale deed is registered.

Until you do, your share of property tax in Kolkata sits inside the building's combined bill. Some developers collect it as part of maintenance. Some do not pay it at all. Apply as soon as your deed is registered, and get your own assessee number. Our guide to mutation, khajna and parcha in West Bengal covers how mutation works in more detail.

Outside KMC: Howrah, Salt Lake, New Town and Hooghly

Not every Kolkata address pays KMC. Howrah has the Howrah Municipal Corporation. Salt Lake and much of Rajarhat fall under the Bidhannagar Municipal Corporation. New Town is administered by NKDA, which charges its own levies. Uttarpara, Konnagar and Serampore each have their own municipality.

Each body has its own assessment rules and payment portal. The principle is the same everywhere: tax follows the property, not the person. If the seller leaves dues behind, you inherit them.

What to check before you buy a flat

Unpaid property tax in Kolkata stays with the flat, so before you pay the token on a resale flat, ask for:

• The latest paid property tax bill and receipt, in the seller's name.
• Confirmation that the flat is separately assessed, not still part of the building's bill.
• Whether the flat is shown as owner-occupied or tenanted, and whether that matches reality.
• A no-dues statement, or at least a printout of the outstanding amount from the KMC site using the assessee number.

For a new flat, ask the developer who pays the tax between possession and your mutation, and get it in writing. It sounds small. It is the kind of small thing that blocks a sale ten years later.

Want us to check the tax position on a flat?

Send us the assessee number or the latest bill for any flat you are considering. We will tell you what is outstanding, whether it is separately assessed, and what your property tax in Kolkata should be once you own it.

See our rentals service, browse verified properties, or talk to our legal and loan help desk. We are a RERA-registered agent, WBRERA/A/HOW/2025/000651. This is general guidance and not legal advice; check the specifics for your property with a professional.