Maintenance Charges, CAM and Sinking Fund Explained 2026

By Gopi, Bangalore Real Estate Desk

Published 20 Jul 2026 · Last updated 20 Jul 2026

The price on the brochure is not the last cost of owning an apartment. Every month the shared parts of a complex, the lifts, the security, the water, the generator and the gardens, cost money to run, and that money comes from the residents as maintenance. Add the funds set aside for big future repairs and a one-time deposit at handover, and the sums are large enough to plan for. If you are buying an apartment on Bannerghatta Road or anywhere in Bengaluru in 2026, this guide explains what maintenance and CAM charges cover, how they are worked out, what the sinking and corpus funds are for, and what to check before you sign.

What Maintenance and CAM Charges Cover

Maintenance charges, often called CAM for common area maintenance, pay to run and upkeep everything you share with your neighbours. In a typical gated apartment complex that includes:

• Security and housekeeping: guards, cleaning of common areas, waste handling.
• Lifts and equipment: servicing and annual contracts for lifts, pumps and gates.
• Power and water: common-area electricity, the diesel generator and its fuel, water supply and the sewage treatment plant.
• Landscaping and amenities: gardens, the clubhouse, gym, pool and play areas.
• Routine repairs: a working buffer for day-to-day fixes in the shared areas.

What it does not cover is your own flat: the interior, your individual electricity and water metering, and your property tax are all yours to pay separately.

How Maintenance Is Calculated

There is no single national rule; the society or builder sets the method and it should be in writing. Three approaches are common:

• Per square foot: a rate multiplied by your flat's area, so a larger home pays more. This is the most widely used method.
• Equal per flat: the same amount for every flat regardless of size, on the logic that everyone uses the shared services similarly.
• Hybrid: basic services split equally and the rest charged by area.

Because the charge often follows the built-up or super built-up area, the same area definitions that affect your price also affect your monthly bill; our carpet vs super built-up area guide explains how those are measured. Ask what the rate is, what it includes, and how often it is revised, since power and wage costs climb over time.

The Sinking Fund and the Corpus Fund

Beyond the monthly running cost, a well-run society keeps reserves for the big, occasional bills. Two terms come up:

• Sinking fund: a long-term reserve built up from small, regular contributions and earmarked for major future work, replacing a lift, repainting the towers, big plumbing or waterproofing jobs, or structural repairs. Setting it aside steadily avoids a sudden lump-sum demand when a large job falls due.
• Corpus fund: usually a one-time amount collected from each buyer at handover, often held as a deposit whose returns help meet costs in the early years before the society is fully self-sustaining.

Both are reserves, but the corpus is a one-off deposit taken up front while the sinking fund keeps growing month by month. Neither should be treated as a red flag; they are how a society stays solvent. Do, though, get the amount and purpose of each in writing.

Charges at a Glance

Amounts and bases vary by project and society. Get the exact figures and method in writing before you buy.

GST and Who Collects the Money

GST can apply to monthly maintenance, but only above thresholds that depend on the charge per member and the society's turnover; small societies and modest charges are typically outside it. The rules change, so treat any figure as indicative and confirm the current position with a chartered accountant. The sinking fund and one-time corpus are treated differently from monthly maintenance, another reason to take professional advice on the numbers.

In the early months after handover, the builder or its facility team usually runs the complex and collects maintenance against an advance taken at possession. Once enough flats are handed over, an owners association is formed and takes over the accounts, the funds and the running of the society. Our possession and handover checklist covers what to collect and confirm on the day you take the keys.

What to Check Before You Buy

• The rate and method: the per-sq-ft rate or flat amount, what it includes, and how often it is revised.
• The one-time sums: the corpus and any advance maintenance due at handover, so they are in your budget.
• The reserves: whether a sinking fund exists and how it is funded.
• The handover of accounts: when the owners association is formed and the funds passed to it.
• Get it in writing: the sale agreement or a maintenance schedule should spell these out; our home buying checklist lists the documents to gather.

Maintenance at Birla Bannerghatta

Birla Bannerghatta is a 50-acre gated township by Birla Estates at Begur, with a clubhouse and amenities that a maintenance budget will run once the community is occupied. As a pre-launch project, the maintenance rate, corpus and advance are not finalised yet; when they are announced, ask for the per-sq-ft basis, the one-time corpus, the advance period, and how the sinking fund and the owners association are planned. Factor the monthly maintenance into your running cost, not just the EMI, when you decide on a unit size.

• Builder: Birla Estates (Aditya Birla Group)
• Location: Begur, Begur Hobli, Bannerghatta Road
• Configs: 1, 2, 3, 3.5 BHK + duplex/villa formats
• Starting price: ~₹75 L (indicative; base ~₹12,500 / sq ft)
• Status: Pre-launch · possession early 2031 · K-RERA expected Mar 2027

See the price list and the floor plans to fix the unit and area, then budget the maintenance around it.

Frequently Asked Questions

1. What do apartment maintenance or CAM charges cover?

CAM pays to run the shared areas and services, security, housekeeping, lifts, generator, common water and power, gardens and amenities, not your own flat.

2. How are maintenance charges calculated?

Most societies charge a rate per square foot of your flat, so a larger flat pays more; some charge equally per flat or use a hybrid of the two.

3. What is a sinking fund?

It is a long-term reserve built from small regular contributions for big future jobs like a lift replacement, repainting or major repairs.

4. What is the difference between the corpus fund and the sinking fund?

The corpus is a one-time deposit taken at handover, while the sinking fund is built up over time for major future repairs and replacements.

5. Is GST charged on maintenance?

GST can apply above thresholds tied to the charge per member and the society's turnover; treat any figure as indicative and confirm with a chartered accountant.

6. Who collects maintenance before the owners association is formed?

The builder or its facility team usually collects it against an advance taken at possession, until an owners association is formed and takes over.

Conclusion

Maintenance is the running cost of owning an apartment, and it is worth understanding before you buy, not after the first bill. Know how the monthly CAM is calculated, what it covers, and how often it is revised. Budget for the one-time corpus and any advance due at handover, and treat a healthy sinking fund as a sign the society plans ahead rather than an unwelcome extra. Get the rate, the funds and the plan for the owners association in writing, and confirm anything about GST with a professional. Do that, and the shared home runs smoothly and your monthly outgo holds no surprises.

Buying on Bannerghatta Road? Review the price list and the floor plans for Birla Bannerghatta at Begur, then budget the monthly maintenance alongside the EMI.