Why It Matters
When a landlord offers "one month free" on a 12-month lease at $2,000/month, the face rent is $2,000 but the effective rent is only $1,833. That $167 gap represents the real cost of filling a vacancy versus what's stated on the lease — and it's what your underwriting should rely on.
At a Glance
- Effective Rent = (Total Lease Value − Concessions) / Lease Term in Months
- Face rent and effective rent diverge whenever concessions exist
- Used to compare competing offers on a level playing field
- Critical for underwriting, NOI calculations, and rent comps
- More honest measure of income than stated rent when the market is soft
Effective Rent = (Total Lease Value − Concessions) / Lease Term in Months
How It Works
The formula is straightforward:
Effective Rent = (Total Lease Value − Concessions) / Lease Term in Months
Start with total lease value — multiply the face rent by the number of months. Then subtract every concession: free-rent periods, signing bonuses, waived fees, or tenant improvement allowances paid by the landlord. Divide the result by the lease term in months to get your effective monthly rent.
Example: A 12-month lease at $2,400/month has a total lease value of $28,800. The landlord offers one free month to attract a tenant. That concession is worth $2,400. Subtract it: $28,800 − $2,400 = $26,400. Divide by 12: $26,400 / 12 = $2,200 effective rent per month.
The same math applies at any scale. On a 24-month commercial lease at $5,000/month with two free months as tenant improvement allowance, total value is $120,000, concessions are $10,000, and effective rent is $120,000 − $10,000 = $110,000 / 24 = $4,583/month.
Investors encounter this metric in three main contexts. First, underwriting acquisitions: when sellers supply rent rolls, face rent can overstate income if concessions are embedded in active leases. Always ask whether quoted rents are face or effective. Second, rent comps: in a soft market, competing properties may advertise $2,500 face rent while quietly offering two free months. Comparing face rents makes their units look more expensive than they are. Effective rent levels the field. Third, renewal negotiations: knowing the effective rent on an expiring lease tells you whether you're re-leasing at a gain or a loss relative to the original underwriting.
The spread between face rent and effective rent also signals market conditions. In tight markets, concessions shrink and the two figures converge. In oversupplied markets, the gap widens as landlords compete for tenants. Watching this spread across your portfolio is an early indicator of vacancy pressure before it shows up in cash-on-cash returns.
Real-World Example
Darnell owns a 6-unit building in a Midwest mid-rise corridor. When he acquired it, the prior owner had signed two leases during a slow winter with "first month free" deals to avoid extended vacancy. Both tenants pay $1,800/month face rent on 12-month leases.
Darnell's acquisition underwriting had used $1,800 as the monthly income for those units. After closing, he recalculates properly: total lease value per unit = $1,800 × 12 = $21,600. Concession = $1,800. Effective rent = ($21,600 − $1,800) / 12 = $1,650/month for the concession period.
The 8.3% gap meant his two concession units were generating $300/month less combined than he had modeled — a $3,600 annual shortfall. Not a deal-killer, but enough to affect his house-hack financing reserves for that first year.
He also learned to look for concession language in every lease before closing — not just the rent figure on the rent roll.
Pros & Cons
- Reveals true income when face rent overstates what's actually collected
- Enables apples-to-apples comparison of competing rental offers
- Improves NOI accuracy during acquisition underwriting
- Surfaces market softness early before it impacts cash flow
- Useful when negotiating primary-residence-loan qualification since lenders often apply haircuts to rental income
- Requires reading every lease to identify all concession types — easy to miss non-obvious concessions like waived application fees or parking credits
- In long commercial leases with step-ups, the calculation becomes more complex and may need month-by-month modeling
- Sellers and listing agents rarely disclose effective rent proactively — you have to ask
- Can be misused to make concession-heavy leases look better than they are if the concession period is still active
Watch Out
Occupancy fraud risk. Some borrowers applying for owner-occupied requirement loans overstate rental income by using face rents rather than effective rents on the income schedule. Lenders reviewing appraisal rent schedules may or may not catch embedded concessions. If you're on the lending side of a deal, request the actual lease documents — not just the rent roll summary. Misrepresenting rental income in a loan application can constitute occupancy fraud.
Concession recapture provisions. Some leases include clawback language: if a tenant breaks the lease early, they owe back the value of any free-rent months received. Know whether your leases have this — it affects how you model risk and what effective rent really means if a tenant churns early.
Watch for stacked concessions. A lease might include a free month, a reduced-rate second month, AND a waived pet deposit. Each is a concession. Add them all before dividing. The formula is the same — concessions is a total figure, not just free-rent months.
One-year occupancy interplay. If you're house-hacking and plan to satisfy the one-year occupancy requirement before converting the unit to a rental, remember that any concessions you offer when you eventually lease the unit will reduce the effective rent used in future refinance income calculations.
The Takeaway
Effective rent is the honest number. Face rent tells you what's printed on the lease; effective rent tells you what hits your bank account on average. Every acquisition underwriting, every comp analysis, and every renewal negotiation should use effective rent — not face rent — as the baseline. The calculation is simple: subtract total concessions from total lease value, divide by months. What you're left with is the income your property is actually delivering.