Contra Costa County · Renting & eviction
Renting in Contra Costa County: the rules that apply
In unincorporated Contra Costa County, the county code limits rent only for mobilehome park spaces and condominium conversions. It has no just-cause or notice rules of its own; state law applies there, and to deposits, harassment, repairs and entry.
Key points
- Mobilehome spaces: County rule: standard mobilehome space increases are the greater of 2% or 75% of the CPI change in any 12 months, at most 6%.
- State rent cap: State law: covered units are limited to 8.8% for increases taking effect August 1, 2026 through July 31, 2027.
- Just cause: The county code has no just-cause rule; state law requires a stated just cause to end tenancies in covered units after 12 months.
- Ending a tenancy: The county has no notice rule of its own; state law requires 60 days' notice to end a tenancy, 30 if under 1 year.
- Vacate orders: County rule: after a county vacate order for an immediate health and safety danger, the owner pays relocation costs as state law requires.
- Condo conversions: County rule: in condominium conversions, all increases in 12 months may total no more than 100% of the San Francisco-Oakland rental CPI change.
Each rule below is marked Contra Costa County code or CA state law and links to the section it comes from (checked October 2026). General information, not legal advice.
Contra Costa County's code applies in the unincorporated areas of the county. Cities in Contra Costa County have their own codes and their own pages.
Rent increases
Contra Costa County code County rule: standard mobilehome space increases are the greater of 2% or 75% of the CPI change in any 12 months, at most 6%. State law: covered units are limited to 8.8% for increases taking effect August 1, 2026 through July 31, 2027. County rule: in condominium conversions, all increases in 12 months may total no more than 100% of the San Francisco-Oakland rental CPI change.
Eviction and just cause
CA state law Contra Costa County has no rule of its own on this, so California law applies. Just cause required: After 12 months of lawful occupancy, the owner may terminate only for a just cause stated in the notice (Civ. Code § 1946.2(a)). Just-cause eviction in California — the full state rule →
Relocation payments
| Amount |
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|---|---|
| When relocation is owed |
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CA state law Underneath, California law still applies. No-fault eviction relocation assistance: One month's rent (as relocation payment or rent waiver), paid within 15 calendar days of the notice (Civ. Code § 1946.2(d)(3)(A)). Relocation under California's just-cause law — the full state rule →
Notices
We found no Contra Costa County rule on this in the Contra Costa County Municipal Code (checked October 2026). The state rule below applies.
| Notice of a rent increase | At least 30 days' notice for an increase of 10% or less; at least 90 days for an increase of more than 10% Applies: The 10% is measured against the rent charged at any time in the 12 months before the increase, counting all increases in that period together. |
|---|---|
| Notice to end a month-to-month tenancy (landlord) | 60 days' notice; 30 days if the tenant has lived there less than one year Applies: Where the unit is covered by just cause (Civ. Code § 1946.2) or a local ordinance, the notice must also state a qualifying cause. |
| Notice to end a month-to-month tenancy (tenant) | At least as long as the rental period (one month for a month-to-month tenancy) |
| 30-day notice when the unit is sold to an owner-occupant | 30 days' notice when a separately sellable unit is in escrow to a natural person who will live there for at least a year Applies: Notice within 120 days of opening escrow, given once, and all § 1946.1(d) conditions met. |
| Notice to pay rent or quit | 3 days, not counting Saturdays, Sundays and judicial holidays, stating the amount due and how to pay Applies: May be served any time within one year after the rent became due. |
| Notice to cure a lease violation or quit | 3 days, not counting Saturdays, Sundays and judicial holidays, to perform the broken lease term or leave |
| No fee for serving notices | A landlord may not charge the tenant a fee for serving or posting a notice |
Security deposits
CA state law Contra Costa County has no rule of its own on this, so California law applies. Security deposit cap: One month's rent, on top of the first month's rent (Civ. Code § 1950.5(c)(1), (c)(6)). Deposit return deadline: 21 calendar days after the tenant moves out, with an itemized statement of any deductions (Civ. Code § 1950.5(h)(1)). California security deposit law — the full state rule →
Retaliation
Contra Costa County code 6 months. Asserting or using rights under the county's mobilehome rent chapter.
All 6 Contra Costa County rules on retaliation, with the code text and the state law underneath →
Harassment and lockouts
CA state law Contra Costa County has no rule of its own on this, so California law applies. Lockouts and self-help eviction banned: A landlord may not change locks, remove doors or windows, or remove the tenant's belongings to force a tenant out (Civ. Code § 789.3(b)). Utility shutoffs banned: A landlord may not cut off water, heat, electricity, gas or other utilities to force a tenant out (Civ. Code § 789.3(a)). Tenant harassment and lockouts in California — the full state rule →
Repairs and habitability
CA state law Contra Costa County has no rule of its own on this, so California law applies. Duty to keep the unit habitable: The landlord must deliver a unit fit to live in and repair conditions that make it untenantable (Civ. Code § 1941). Repair and deduct: A tenant may make a repair the landlord neglects and deduct the cost from rent, up to one month's rent, no more than twice in any 12 months (Civ. Code § 1942(a)). Habitability and repair-and-deduct — the full state rule →
Landlord entry
CA state law Contra Costa County has no rule of its own on this, so California law applies. Landlord entry notice: Reasonable written notice, presumed to be 24 hours, and entry only during normal business hours (Civ. Code § 1954(d)(1), (e)). Landlord entry notice in California — the full state rule →
Short-term rentals
| Allowed |
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| Cap on rentals |
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| Nights per year |
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| Permit or registration |
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Hotel and short-term rental tax
| Tax rate |
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| Who collects it |
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Condo conversions
| Relocation help |
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|---|---|
| Notice to tenants |
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Other Contra Costa County rules on this
Contra Costa County's code also has these chapters. We have not summarized their values on this page yet; read them in the library.
- Special Leases and Rent Increase (Ch. 926-14) — condominium conversions only
- Mobilehome Space Rent (Ch. 540-2) — mobilehome park spaces only
- Mobilehome Space Rent (§ 540-2.1406) — mobilehome park spaces only
Who this affects
Frequently asked questions
Does a landlord in Contra Costa County need a reason to evict?
The county code has no just-cause rule; state law requires a stated just cause to end tenancies in covered units after 12 months.
Does a Contra Costa County landlord have to pay relocation?
County rule: after a county vacate order for an immediate health and safety danger, the owner pays relocation costs as state law requires.
How much notice does a Contra Costa County landlord have to give?
The county has no notice rule of its own; state law requires 60 days' notice to end a tenancy, 30 if under 1 year.
How much can a Contra Costa County landlord charge for a security deposit?
Contra Costa County has no local rule on this that we found (checked October 2026); state law applies: One month's rent, on top of the first month's rent (Civ. Code § 1950.5(c)(1), (c)(6)).
Can I rent out my home short-term in Contra Costa County?
Contra Costa County's code: Yes, with a short-term rental permit. Units in buildings with 5 or more homes may not be rented short term. (Applies to hosted and non-hosted short-term rentals, with 1 rental per lot.) (§ 88-32.602); No more than 1 short-term rental on any lot. (§ 88-32.602).
What is the hotel tax on short-term rentals in Contra Costa County?
Contra Costa County's code: Hotel guests pay a tax of 10% of the rent. (Applies to hotel stays, as a percent of the rent the operator charges.) (§ 64-4.402); The operator collects the tax from each guest when the rent is collected. (§ 64-4.406).
What happens to tenants when a Contra Costa County building converts to condos?
Contra Costa County's code: The subdivider pays 3 times the monthly rent for moving expenses. (Only to a tenant who was entitled to notice, did not get it, became a tenant, and did not buy their unit.) (§ 926-10.206); Each new rental applicant gets notice of the filing, starting at least 60 days before the tentative map is filed. (Applies to each person who applies to rent a unit after that date, before any rent or deposit is accepted.) (§ 926-10.206).
General information, not legal advice.
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