Calculate true monthly rent after free months and concessions. Compare apartments with different incentive packages and see which deal saves you more over the full lease.
Net effective rent (NER) is the true average monthly cost of a lease after spreading all concessions — free months, moving credits, broker fee waivers — evenly across the lease term. A $3,000/month apartment with 2 free months on a 14-month lease has a net effective rent of ($3,000 × 12) ÷ 14 = $2,571/month, a 14.3% discount from the advertised price.
Landlords in competitive markets frequently offer concessions instead of lowering the listed rent, because it preserves the building's rent comparables (comps) and makes future rent increases less dramatic. New York City luxury buildings routinely offer 1-4 free months on 12-16 month leases, creating net effective discounts of 7-28%.
But be careful: when your lease renews, the renewal price is based on the gross rent (not the net effective), so next year's rent of $3,000 feels like a massive increase from the $2,571 you were effectively paying. This calculator helps you compare apartments with different concession packages, see the true cost difference, and understand what you'll pay at renewal.
Use this calculator when listings advertise concessions instead of lowering the sticker rent. It helps you compare deals on the same monthly basis and see how much of the headline discount is real savings now versus rent that snaps back to the gross amount at renewal.
Net Effective Rent = (Gross Rent × Paid Months − Other Concessions) ÷ Total Term Paid Months = Lease Term − Free Months Total Concession Value = (Gross Rent × Free Months) + Other Concessions Effective Discount = (Gross − Net Effective) ÷ Gross × 100
Result: Net Effective Rent: $2,292/mo — 8.3% discount — Save $2,500 total
Gross total = $2,500 × 12 = $30,000. Free month value = $2,500. Effective total = $27,500. NER = $27,500 ÷ 12 = $2,292. Monthly savings = $208. Next year gross rent stays $2,500 though.
Landlords often prefer concessions over reducing the listed rent because a higher gross rent supports future renewals and preserves building comparables. For renters, that means the marketed monthly number can overstate what the lease actually costs in year one.
The main catch with free months is that they usually disappear at renewal. If you signed based on the net effective monthly cost, the next lease can feel like a sudden jump even when the landlord keeps the gross rent flat or raises it only slightly. That is why comparing gross and net side by side matters before signing.
Two apartments can have very different gross rents and still land at similar net effective rents once free months, move-in credits, and broker-fee waivers are included. The best deal depends not only on the year-one average but also on whether you expect to renew, move quickly, or prioritize lower upfront cash needs.
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This page calculates total gross lease cost as gross monthly rent × lease term, values free months at the gross monthly rent, subtracts any entered moving credits, broker-fee waivers, parking credits, and other concessions, and then divides the reduced total by the full lease term to produce net effective rent. It also compares that result with a lower gross-rent offer so the user can compare year-one economics on the same monthly basis.
The net effective figure is a cash-flow worksheet, not a legal rent ceiling. Renewal rent, broker-fee rules, concession timing, and fee disclosures depend on the actual lease and local law, so the worksheet should be used to compare offers rather than to interpret landlord obligations.
Net effective rent is the true average monthly cost of a lease after spreading all concessions across the full term. If gross rent is $3,000 with 1 free month on 12 months: NER = ($3,000 × 11) ÷ 12 = $2,750. It's the only way to compare apartments with different incentive packages.
Usually yes, because: (1) Renewal is based on gross rent, so free months don't carry forward. (2) Lower gross means lower renewal increases. (3) Lower gross reduces broker fees (usually 1 month or 15% of annual rent). However, some landlords won't lower gross rent but will give free months — in that case, free months are better than nothing.
Varies by market condition. In soft NYC markets: 1-4 free months on new leases. In most US cities: 0-1 free months. New luxury developments use concessions most aggressively. In tight markets (2-3% vacancy), concessions disappear entirely.
Yes. If your net effective was $2,500 but gross was $3,000, your renewal will be based on $3,000 (often with a 2-5% increase). So you might pay $3,000-3,150 in year 2 — feeling like a $500-650 increase from what you were effectively paying. Factor this into your comparison.
A shorter lease with more free months (per month) might have better NER, but you risk: higher renewal rates, moving costs sooner, and broker fees again. Usually a longer lease with proportional concessions provides more stability. The term comparison table shows the exact economics.
Broker fees are typically based on the gross annual rent (commonly 1 month or 15% of annual). Concessions don't reduce the fee. Some landlords waive the broker fee as part of the concession package — this should be included in your NER calculation.