One common question from those looking for investment properties in San Francisco is how to calculate rental yields. It's easy to judge based solely on the purchase price, but simply put, it involves determining how much net operating income is generated relative to the purchase price. This ratio is called the cap rate.

Starting with rental levels, the average rent in San Francisco is $4,346 per month as of August 15, 2026 (Zumper). The median rent for a two-bedroom apartment has risen to $6,020, surpassing New York's median rent of $5,450. This figure represents a 24% increase over the past year. Applying the 1% rule, which gauges whether you can receive more than 1% of the purchase price in monthly rent, shows that due to the high purchase prices, it's difficult to meet this standard compared to other areas.

For example, properties with a net operating income of 4% and 6% of the purchase price may have the same rent, but their investment characteristics are completely different. In a market like San Francisco, where purchase prices are high, it's common for rental yields to be lower than in other areas, even if rents are high. This suggests an investment strategy that places more weight on long-term capital appreciation rather than rental income.

To simplify the cap rate, it is the value obtained by dividing net operating income by the purchase price. Even if rents are high, if the purchase price increases at a higher rate, the cap rate can actually decrease. Therefore, it's important not to focus solely on the rent number, but to compare the net income after deducting management fees, property taxes, and insurance.

It's also essential to consider rental laws. The San Francisco Rent Ordinance (Chapter 37) applies to buildings with two or more units built before June 13, 1979, while single-family homes, condos, and townhouses are exempt under the Costa-Hawkins Act. If applicable, the annual increase cap from 2025 to 2026 is set at 1.4%, based on 60% of the Bay Area's inflation rate. Evictions can only occur for one of the 16 specified just causes. Checking whether the property is subject to these regulations is crucial for planning rent increases.

If you plan to purchase a property subject to these regulations, it's important to first check how much lower the current rent of existing tenants is compared to the market rate. Long-term tenants often have a significant gap between their actual rent and the market rent, and this gap is reflected in the cap rate calculation.

Loan conditions also differ from owner-occupied properties. Investment loans typically require a down payment of 15% to 25%, and while a credit score of 620 is sufficient for consideration, a score of 740 or higher is needed for favorable rates. Interest rates are also set 0.5 to 0.75 percentage points higher than those for owner-occupied loans (according to Fannie Mae and Freddie Mac). Banks only recognize up to 75% of rental income as qualifying income.

Annual expenses must also be taken into account. The effective property tax rate in San Francisco County is approximately 0.71%. Landlord insurance is typically higher than standard homeowners insurance, and if you hire a property manager, 8% to 12% of the rent will go to management fees. It's common to set aside about 1% of the property value annually for maintenance. For regulated properties, failing to manage them directly can lead to increased dispute costs, so many investors choose to hire property management. When selling later, a 1031 exchange can be used to defer capital gains tax.

Ultimately, rather than judging this area based solely on the rental yield number, it's important to consider the regulatory status, purchase price, and annual expenses together to get a complete picture. In simple terms, high rents do not necessarily mean high yields. This article is not investment or legal advice, and it is recommended to consult with a professional to review individual circumstances before making any agreements.