KMC Mutation and Property Tax in Kolkata: Complete Guide 2026

For every property owner in Kolkata, the Kolkata Municipal Corporation (KMC) is the primary civic authority for property mutation, assessment of property tax and the levying of cesses. Whether you have bought a flat in Salt Lake, inherited a house in Behala, or are developing a commercial premises on Park Street, you will need to deal with KMC's Assessment Department. This guide explains the KMC mutation process, the calculation of property tax through the Assessed Annual Value (AAV), and the procedure for filing objections — all as they stand in 2026.

KMC Mutation: What It Is and When You Need It

KMC mutation is the process of updating the municipal records to reflect a change in ownership or in the structure of the property. It is distinct from mutation of land records done at the BL&LRO under the West Bengal Land Reforms Act — KMC mutation deals with the municipal holding for the purpose of property tax assessment.

You must apply for KMC mutation when:

• A property is bought or sold (mutation in the purchaser's name).
• Ownership passes by gift, exchange or partition.
• A property is inherited (mutation in the name of the legal heirs, with succession certificate or probate where required).
• The structure is altered — new construction, addition of a floor, change in use (residential to commercial), demolition.
• A leasehold interest of 12 months or more is created.

How to Apply for KMC Mutation

1. Online portal: Visit the KMC citizen services portal and navigate to the Mutation / Assessment section. The online application has been progressively expanded and now covers most holdings within the KMC area.
2. Required documents:
   • The deed of conveyance, gift, exchange or partition (original + self-attested copy).
   • Previous municipal bill and the holding number.
   • Mutation certificate or Khatian from the BL&LRO where applicable (for land-bearing properties).
   • Building plan/sanction and completion certificate where there is new construction or alteration.
   • Succession certificate, probate or letters of administration in inheritance cases; indemnity bond and affidavits from the heirs.
   • Identity and address proof of the applicant(s).
3. Fees and charges: KMC charges a mutation fee (typically a percentage of the AAV or a fixed fee per case) plus the transfer fee. The quantum is fixed under the Kolkata Municipal Corporation Act, 1980 and the schedules made thereunder.
4. Site inspection: The Assessment Department may conduct a physical inspection to verify the structure, use and dimensions.
5. Order of mutation: On satisfaction, the Municipal Assessor issues the mutation order and updates the holding in the name of the new owner, with the revised assessment.

Property Tax in Kolkata: The Assessed Annual Value (AAV)

KMC property tax is levied on the Assessed Annual Value (AAV) of a holding. The AAV is computed under the KMC Act, 1980 (as amended, most significantly by the Kolkata Municipal Corporation (Amendment) Act which introduced the Unit Area Assessment method — UAA). The UAA system replaced the old rental-based valuation with a formulaic approach.

The Unit Area Assessment (UAA) Formula

Under UAA, the annual value of a property is calculated as:

AAV = (Covered Area) × (Base Unit Area Value) × (Use Factor) × (Occupancy Factor) × (Age Factor) × (Structure Factor) × (Rate of Coverage/Land)

• Base Unit Area Value: A rate assigned per square metre to each ward/zone, fixed by KMC notification.
• Use Factor: Distinguishes residential, commercial, industrial and mixed-use properties; commercial attracts a higher factor.
• Occupancy Factor: Owner-occupied vs. tenant-occupied (let out properties attract a higher factor).
• Age Factor: Reduces value for older buildings.
• Structure Factor: Reflects the quality of construction (pucca, semi-pucca, RCC, etc.).
• Covered Area / Land Area: The built-up or land area on which the rate is applied.

The total property tax is then a percentage of the AAV, comprising the general rate, a conservancy rate, a water rate and the education cess and health cess as notified.

Quarterly Bills and Online Payment

• KMC issues property tax bills on a quarterly cycle — April-June, July-September, October-December and January-March.
• Payment can be made online through the KMC portal using UPI, net banking or cards, or at designated KMC counters and banks.
• An on-account payment option is available when there is a dispute about the exact demand.
• Interest and penalties accrue on delayed payment at the rate notified under the KMC Act.

Filing an Objection or Revision Petition

If you believe the assessment is incorrect — wrong use factor, wrong area, wrong age or a mismatch with the actual structure — you can challenge it. The procedural route under the KMC Act is:

1. Objection before the Municipal Assessor / Assessment Department within the period prescribed (ordinarily 30 days) of the assessment/revision notice. The objection must set out the grounds and supporting documents (sanctioned plan, sale deed, photographs).
2. Re-assessment order: The Assessor considers the objection, may inspect the property, and issues a revised assessment order.
3. Appeal to the Municipal Assessment Tribunal / Appellate Authority: If the objection is rejected, an appeal lies to the tribunal/appellate authority constituted under the KMC Act, within the limitation period.
4. Further remedy: Where a question of law is involved, the matter can be carried further under the writ jurisdiction of the Calcutta High Court under Article 226 of the Constitution.

Common grounds for objection include: incorrect classification of use, incorrect covered area, failure to apply the age or structure factor, assessment of common areas, and assessment of structures that have been demolished or are in dangerous condition.

Self-Assessment and Rebates

• Self-assessment scheme: KMC offers a self-assessment facility for certain residential properties, allowing owners to declare their details and pay the computed tax online, with verification carried out later.
• Rebate for prompt payment: A rebate (commonly 5%) is offered on the annual tax if the entire year's tax is paid in advance within the notified date in the first quarter.
• Exemptions: Certain properties — places of public worship, charitable institutions, government property — may be exempt under the KMC Act, subject to conditions.

Practical Tips for Kolkata Property Owners

• Apply for mutation as soon as the sale deed is registered — delays attract compounding fees and complicate tax payment.
• Keep the sanctioned building plan and completion certificate ready; unauthorised construction attracts a higher factor and enforcement.
• Where the property is let out, factor in the higher occupancy factor when budgeting tax.
• Review the annual bill each year for any unexplained revision in the AAV.
• For inherited properties, obtain the mutation in the heirs' names promptly to avoid disputes and to enable later sale or mortgage.

Common Disputes and Litigation Before the Calcutta High Court

KMC assessment disputes frequently reach the Calcutta High Court under its writ jurisdiction (Article 226). Typical challenges include: arbitrary enhancement of the AAV without a fresh survey, misclassification of a residential property as commercial, levy of tax on common areas of apartment complexes, and refusal to mutate despite valid documents. The High Court has, in several decisions, emphasised that the AAV must be computed strictly on the basis of the notified factors and that any departure must be supported by reasons. Where a property owner is faced with an unexplained or unlawful demand, approaching the High Court after exhausting or being denied the statutory remedies of objection and appeal can secure quashing of the demand and a direction for fresh assessment.

Frequently Asked Questions