The formula, first
Daily rate = (monthly rent × 12) ÷ 365
Everything else follows from that one line, and it is the arithmetic behind every offer move-in specials prices.
- Daily rate × days in the lease = gross lease cost
- Daily rate × free days = concession value
- (Gross − concession) ÷ lease months = effective monthly rent
Step one is always the day count
Concessions are quoted in units that do not convert cleanly to months. Convert them first.
| Quoted as | Days free |
|---|---|
| Four weeks free | 28 |
| Six weeks free | 42 |
| Eight weeks free | 56 |
| Free February | 28 |
| Free April | 30 |
| Free July | 31 |
| One month free (generic) | ~30.4 |
| Two months free (generic) | ~60.8 |
“Six weeks free” and “a month and a half free” differ by about 3.6 days. At a $50 daily rate that is $180, and it is the kind of gap that decides a comparison between two close offers.
Worked: six weeks free
$1,500 rent, 12-month lease, six weeks free.
- Daily rate: (1,500 × 12) ÷ 365 = $49.32
- Lease days: 365
- Gross lease cost: 49.32 × 365 = $18,000
- Free days: 42
- Concession value: 49.32 × 42 = $2,071
- Net lease cost: 18,000 − 2,071 = $15,929
- Effective monthly: 15,929 ÷ 12 = $1,327
The sign says $1,500. You average $1,327. That is the number to carry into any comparison — see net effective rent for the full definition.
Do not average the free weeks into months
“Six weeks free over twelve months is about half a month off each” is close enough to feel right and wrong enough to misrank two offers. Do the days. The same trap is why a free February is worth less than a free July.
What the effective rent does not cover
Fees. Amenity, parking, package, valet trash, pest, pet rent, RUBS, and bulk internet are recurring and untouched by any concession. Add them after.
The clawback. If breaking early makes the free rent repayable, your effective rent is conditional on completing the term. Read the concession addendum.
Renewal. Concessions apply to year one. Month thirteen resets toward market.
All three sit in the same place: move-in specials runs them together on every offer we price.
Longer terms and partial months
Two complications come up regularly.
Non-12-month terms. A 15-month lease has roughly 456 days. Use the actual term length in step one; the daily rate does not change.
Prorated first month. If you move in mid-month, the first month is prorated at the daily rate. That is the same number, used for a different purpose, and it is worth checking the property calculates it the same way.
Where this gets used
Any time you have two offers with different terms or differently-worded concessions. Convert both, add both fee stacks, and the comparison becomes a subtraction.
Send us the offers and we will do it, with a verification date on every figure.