California Security-Deposit Refund Calculator

This free security deposit refund calculator takes the guess-work out of the 21-day security deposit rule. Enter your move-out date—plus any extra days you and the landlord agreed on—and get an instant California security deposit deadline. Perfect for tenants, property managers, and small-claims preparations. Local ordinances can set stricter timelines—double-check if you live in a rent-controlled city.

Learn All Deposit Rules
Tenant marking the 21-day security deposit refund deadline on a wall calendar

21 Calendar-Day Rule Landlords must refund or send an itemized deduction letter within 21 calendar days of you handing over the keys.

Mail or Hand-Deliver The refund can be mailed or given in person, but the postmark must still fall on or before Day 21.

Receipts Over $125 Deductions greater than $125 require copies of repair invoices or estimates to be enclosed.

Penalties up to 2× Civil Code §1950.5 allows courts to award up to twice the deposit if the landlord withholds in bad faith.

Calculate Your Exact Refund Deadline

Your landlord must send the refund or itemized deductions by:

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Timeline Breakdown

    Why 21 Calendar Days?

    The 21-day security deposit rule comes straight from California Civil Code §1950.5(f). Lawmakers chose 21 calendar days—rather than business days—to keep landlords from holding deposits indefinitely while still allowing enough time to gather invoices and prepare an accounting. Whether you left the unit spotless or anticipate deductions, the clock protects both sides by ensuring a quick financial wrap-up. A landlord may request additional days in writing, but you must agree. Record that agreement in an email for proof.

    How the Clock Starts

    Day 0 begins when you actually surrender possession—usually the moment you return all keys, fobs, and remotes. It is not the lease expiration date if you move out early. Handing keys to an on-site manager at 4 p.m. on June 1 means the deadline falls on June 22. Mail delivery is counted; weekends and holidays do count because the law specifies calendar days. If the landlord insists on a different “move-out” date, keep a written record and photo of the key hand-off to avoid disputes.

    What If the Deadline Is Missed?

    Missing the statutory deadline converts leverage to the tenant. California courts often presume bad faith when a refund is late, unlocking penalties up to twice the deposit amount. Use these action steps if the clock runs out:

    Common Mistakes Tenants Make

    Even savvy renters miss critical steps that undermine their deposit claim. Avoid these pitfalls to keep every dollar on your side:

    • Leaving without written proof of key return. A photo of the key hand-off or a quick confirmation email establishes Day 0 and prevents timeline disputes.
    • Skipping the forwarding address. Civil Code §1962 requires you to give an address. If you forget, the landlord can legally mail to the unit you just vacated, delaying receipt.
    • Packing before documenting condition. Shoot “wide-medium-close” photos before boxes obscure walls and floors; otherwise you may lose evidence that damage was pre-existing.
    • Ignoring deductions under $125. Small charges add up. Request receipts regardless of amount so you can challenge vague “cleaning” or “touch-up paint” line items.
    • Using deposit for last month’s rent without agreement. Unilateral withholding can trigger a negative credit report and jeopardize future rentals.

    Frequently Asked Questions

    Yes. California Civil Code §1950.5(f) uses calendar days, so Saturdays, Sundays, and holidays are part of the 21-day count. If your move-out date is Friday, Day 1 is Saturday but skips to Monday, making Tuesday the first lawful filing day. While you cannot compel a landlord to issue a check on a Sunday, the law still requires the refund to be mailed or hand-delivered by Day 21. If the date falls on a postal holiday, a postmark from the next business day may be acceptable, but courts scrutinize delays—keep the envelope as proof.

    No. The California security deposit deadline is the same 21 days regardless of delivery method. What changes is the proof. If the landlord mails the check, the postmark must be on or before Day 21. Certified-mail receipts give tenants clear evidence. Hand-delivery requires a timestamped receipt or a witness. If the landlord claims they “mailed it,” ask for the tracking number. An untimely postmark can invalidate deductions and expose them to penalties. Always retain the envelope; courts accept the USPS cancellation stamp as decisive proof of lateness.

    The 21-day clock starts when you actually surrender possession, which is normally the key return date—not the day you finished moving furniture. If you stayed until May 5 to clean but handed keys over on May 7, count from May 7. Make sure to document the hand-off: a quick email confirmation or a photo of the keys on the manager’s desk stamps the moment. If the landlord refused the keys, mail them certified; the delivery date becomes Day 0.

    Civil Code §1950.5 allows landlords to apply the deposit to unpaid rent, but they still must provide a full accounting within 21 days. They cannot simply keep your money without explanation. If rent owed exceeds the deposit, you may receive a balance-due statement. However, landlords frequently miscalculate rent or tack on late-fees not permitted by your lease. Scrutinize the itemization and request receipts for each charge. If numbers look inflated, you can contest them in small claims for security deposit disputes. Courts often favor tenants who present ledgers, bank statements, and a written demand letter.

    Yes, but start by requesting the missing documentation in writing. California requires receipts or invoices for any individual deduction over $125. If your landlord fails to provide them within a reasonable time—courts often accept 10 business days—you can argue bad-faith withholding. Courts may award up to two times the deposit as a penalty. Remind the landlord that the itemized security deposit deduction letter sample on our site meets the statutory format, so excuses rarely hold up before a judge.

    No California city currently alters the baseline 21-day rule; local authorities may, however, impose additional tenant protections, such as mandatory interest on deposits or quicker timelines for specific deductions. San Francisco and Berkeley, for example, publish interest tables but still follow the state’s 21-day clock. Always check our interest calculator for city-specific add-ons, but keep counting the calendar days the moment you hand over the keys.

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