San Diego County

San Diego, CA

A market where transfer costs are low and the city once offered one of the most generous ADU programs in California. The 2025 rollback of that bonus program, plus Mello-Roos taxes in newer developments, make the details of each lot matter.

💡 Upside tip

Do not assume the old unlimited ADU bonus still applies: since the 2025 rollback, bonus ADUs are reportedly capped by lot size (4 to 6) and removed in several single-family zones. Check the parcel's zone and transit status in the city's zoning portal, and ask for any Mello-Roos notice before you price the home.

Offers & competition

California purchase contracts default to 17-day investigation, appraisal and loan contingencies, and escrow typically runs about 30 days. The research behind this guide has no San Diego-specific data on offer deadlines or waiver rates.

Closing & who pays

Escrow and title companies close sales; no attorney is required. The seller typically pays the county transfer tax, while title-cost custom varies across San Diego County.

Transfer taxes

Only the county documentary transfer tax of $1.10 per $1,000 (0.11%) applies; the City of San Diego adds no city transfer tax.

Seller disclosures

Statewide California rules apply: the TDS, the Natural Hazard Disclosure (NHD), the agent's AVID and, importantly here, any Mello-Roos or 1915 Act special-tax notice, which the seller must make a good-faith effort to obtain and deliver.

What you can build

State ADU, JADU and SB 9 rules apply. The city's 2020 ADU Bonus Program once allowed unlimited bonus ADUs near major transit in exchange for affordable units, but revisions effective around August 22, 2025 removed bonus eligibility in several single-family zones and reportedly cap bonus units at 4, 5 or 6 by lot size.

Permits & records

Permit history is available through the city's Development Services online records, and zoning through its parcel information portal. No official 2026 median review time was found, so check the city's permit portal for current timelines.

Property tax

Prop 13 resets the assessed value to the purchase price, then caps increases at 2% a year; Mello-Roos and other special assessments, common in newer San Diego developments, push effective rates above the roughly 1.1% to 1.3% base range. Expect a supplemental bill after closing.

Rent rules

There is no local rent control beyond state AB 1482 (5% plus regional CPI, 10% maximum, with just-cause eviction). The city's 2023 Tenant Protection Ordinance adds larger relocation payments for no-fault evictions.

Key risks

Key hazards include the Rose Canyon fault, coastal bluff erosion and wildfire in the canyons; read the NHD report and check fire hazard maps before planning additions.

⚠ Still verifying

The post-rollback ADU bonus caps (4, 5 or 6 by lot size) are quoted by a contractor, not official code; confirm against the city's Information Bulletin 400. Complete Communities amendments, closing-cost customs, the Tenant Protection Ordinance details and the hazard list come from background knowledge and need confirming.

Official sources

Updated: 2026-10 · Summaries of public rules as of the date shown. Not legal or tax advice. Always confirm with the official source.