Rent Rules Explained
Proration, caps, deposits and late fees in one plain-English overview.
Guides Hub
Every guide below is free, with no sign-up. Start with the question you have, then use the matching calculator to run your own numbers — and check the official source for your state before acting.
All rent guides
How to Calculate Prorated Rent
Three methods with worked examples for move-in and move-out.
30-Day vs Actual-Days Proration
Which method costs less, and which is fairer, month by month.
How to Split Prorated Rent With Roommates
Split by days lived in the unit, with a worked roommate example.
Prorated Rent When Breaking a Lease Early
How the final month is handled when a lease ends early.
Is My Rent Increase Legal?
Check caps, timing and notice before accepting an increase.
Washington Rent Cap
HB 1217: 7% plus CPI, capped at 10%, after the first 12 months.
How Much Security Deposit Can a Landlord Charge?
State limits compared, starting with California and Texas.
California Security Deposit Refund
AB 12, the 1-month limit, and the 21-day return rule.
California Missed Security Deposit Deadline
What happens after the 21-day deadline passes.
Texas Security Deposit Deadline
The 30-day rule and the forwarding-address trigger.
Security Deposit Return Deadline
When you should get your money back, state by state.
Late Fee Grace Period
When a landlord can charge a late fee, and when they cannot.
Oregon Late Fee
ORS 90.260, the 4-day grace period, and the 5% structure.
3x Rent Rule Explained
Required-income formula, plus the separate 40x annual test.
Rent Affordability and the 30% Rule
The maximum-rent formula, with its limits explained.
Mid-Term vs Short-Term vs Long-Term Rentals
How 1–12 month stays compare with shorter and longer lets.
Rent per Square Foot Explained
Formula and comparisons for judging value per square foot.
Net Effective Rent vs Gross Rent
Formula and examples after free months and concessions.
First and Last Month's Rent Explained
What move-in cash really covers, and what it does not.
How to use this hub
- Choose the guide that matches your question — partial month, increase, deposit, late fee, affordability, or renewal.
- Read the worked example, then run the matching tool with your own lease figures.
- Compare the result with your lease method, then check the official source for your city and state before acting.
Last verified: 2026-10-25. See Methodology for how rules are verified. This is general information, not legal advice. City ordinances may be stricter and may override state rules.