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Do You Need a Guarantor in SF?

Understanding co-signers, when you need one, and your alternatives.

8 min readUpdated January 2026

If your income doesn't meet the typical 2.5-3x rent requirement, you might need a guarantor. Here's how guarantors work in SF, when you need one, and what to do if you don't have a family member who can help.

What Is a Guarantor?

A guarantor (also called a co-signer) is someone who legally agrees to pay your rent if you can't. They're not living in the apartment—they're just financially responsible as a backup.

Guarantor vs. Roommate vs. Co-Tenant

Guarantor/Co-signer

Financially responsible but doesn't live there. Usually a parent or relative.

Co-Tenant

On the lease and lives there. Equally responsible for rent.

Roommate (Subtenant)

Lives there but may not be on the main lease. Pays you, not the landlord.

When You Might Need a Guarantor

  • Income below 2.5-3x rent — Most SF landlords require this ratio
  • New job / recent start — Limited pay stub history
  • Self-employed / freelance — Variable or hard-to-verify income
  • Student — Limited or no income
  • New to the US — No US credit history
  • Poor credit — Below 650-700 depending on landlord

Typical Guarantor Requirements

The guarantor usually needs to meet stricter standards than the tenant:

Common Guarantor Requirements

  • • Income of 80-100x monthly rent (sometimes higher)
  • • Good credit score (700+)
  • • US-based (some landlords require California resident)
  • • Provide same documents as tenant (ID, pay stubs, tax returns)
  • • Sign the lease or a separate guarantor agreement

What If You Don't Have a Guarantor?

Option 1: Institutional Guarantor Services

Companies that act as your guarantor for a fee:

Insurent

One of the largest. Typically charges about one month's rent annually.

insurent.com →

The Guarantors

Flexible options, works with many buildings.

theguarantors.com →

Rhino

Also offers security deposit insurance.

sayrhino.com →

Cost of Institutional Guarantors

Typically costs 50-100% of one month's rent per year. For a $3,000/month apartment, expect to pay $1,500-3,000. This is non-refundable.

Option 2: Offer More Upfront

  • Larger security deposit — Some landlords accept 2 months instead of 1
  • Prepay rent — Offer to pay several months upfront
  • Higher rent — Some landlords negotiate for less risk

Option 3: Find Flexible Landlords

  • Smaller landlords — Individual owners may be more flexible than big management companies
  • Rent-controlled buildings — Sometimes have less strict requirements
  • Sublets — Current tenant is already on the lease

Tips for Using a Guarantor

  • Ask your landlord first — Not all accept guarantors, especially out-of-state
  • Have guarantor documents ready — They'll need to provide paperwork too
  • Understand the legal responsibility — Guarantors can be sued for unpaid rent
  • Consider the relationship — This is a big ask. Don't put family in a bad position.

Important Warning

If you stop paying rent, your guarantor is legally responsible. This can damage credit and relationships. Only ask someone who truly understands and accepts this risk.

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