Free calculator
Rent or buy a purifier?
Put in your own rental quote and your own service cost, and this tells you the exact month at which buying overtakes renting — with every line of the arithmetic on screen, so you can disagree with an assumption rather than with the answer.
Rent vs buy — your numbers
Result
On these numbers, renting stays cheaper for the whole period — buying does not catch up within ten years.
Over 60 months, renting costs ₹8,360 less. Buying: ₹35,900. Renting: ₹27,540.
If you buy
| Line | Amount | Basis |
|---|---|---|
| Purchase price | ₹14,000 | One-off |
| Installation | ₹800 | One-off |
| Service & consumables (5.0 yrs) | ₹17,500 | ₹3,500/year |
| Electricity | ₹3,600 | ₹60/month |
| Total | ₹35,900 |
If you rent
| Line | Amount | Basis |
|---|---|---|
| Joining / installation | ₹0 | One-off |
| Rental (60 months) | ₹23,940 | ₹399/month |
| Electricity | ₹3,600 | ₹60/month |
| Refundable deposit | ₹0 | ₹1,000 held, excluded as refundable |
| Total | ₹27,540 |
What this calculation does not capture
- · Breakdown risk sits with the rental provider. If a membrane fails in month 14 you pay nothing; if you own it, you pay. That is worth something and the arithmetic cannot price it.
- · A rented unit is removed when you leave. If you move often, or rent your home, that matters more than the crossover month.
- · Owning means you decide when parts are replaced and whether they are OEM. Renting means you do not, which is a cost or a benefit depending on how you feel about it.
- · The deposit is excluded as refundable, but it is capital you cannot use in the meantime.
Purifier rental has grown quickly in Indian cities, and the pitch is straightforward: no capital outlay, no servicing to remember, no repair bills. All three are true. What is usually left unsaid is the point at which the monthly payments exceed what buying the same machine and maintaining it would have cost.
That point is not fixed, and it moves further than people expect on small changes to the inputs. A household paying ₹399 a month against a ₹14,000 unit reaches it at a very different time from one paying ₹599 against a ₹9,000 unit — and the annual service figure, which almost nobody knows before they own a purifier, moves it more than either.
The calculator is deliberately built around your numbers rather than ours. Put your actual rental quote in, put a realistic service figure in, and the crossover follows. Where you do not know the service figure, our filter price index puts a domestic RO system at roughly ₹1,800 to ₹5,500 a year depending on your water and whether parts are OEM.
When renting is genuinely the better decision
This page is not an argument for buying. There are situations where rental is the right answer even well past the crossover month, and they are worth stating plainly:
- You rent your home or move frequently. A rented purifier is collected. An owned one has to be uninstalled, transported, reinstalled and often re-plumbed, and something usually breaks in the process.
- You do not yet know your water. On an unfamiliar borewell, membrane life is genuinely unpredictable. Renting transfers that risk to someone who has priced it across a portfolio.
- Capital is the constraint. Converting a ₹14,000 outlay into ₹399 a month is a legitimate reason, not a lesser one.
- You will not maintain it. An owned purifier whose filters are changed two years late is worse than a rented one serviced on schedule — and the honest question is what you will actually do, not what you intend to.
Methodology
- Buying is modelled as purchase price plus installation, both one-off, plus annual service and consumables accrued monthly.
- Renting is modelled as any joining or installation fee plus the monthly rental, with the refundable deposit excluded from totals and disclosed separately.
- Electricity is applied identically to both models. Because it is identical it cancels out of the crossover entirely, and it is excluded from the breakeven calculation while appearing in both totals.
- Breakeven is the first month at which the cumulative cost of buying is less than or equal to the cumulative cost of renting.
- Nothing is discounted for the time value of money. Over the two-to-three-year horizon that decides this question, discounting changes the crossover by less than the uncertainty in the service-cost input.
- Non-cash factors — breakdown risk transfer, portability, control over parts — are listed but never converted into a rupee figure, because doing so would be inventing a number.
Default values are indicative Indian market figures for illustration, last reviewed 2026-08-08. The calculation is only as good as the numbers you put into it — in particular the annual service figure, which is the input that moves the answer most and the one people are least likely to know before they have owned a purifier for a year.