Obtain Separate Address for Your ADU
A separate address legitimizes your ADU as an independent dwelling. It enables tenants to receive mail and packages, register to vote, set up utilities in their name, and establish residency—all essential for making your rental feel like a real home.
Quick Summary
Processing time
2-6 weeks
Cost
$0-100 (varies by city)
Key contact
City addressing dept.
Why a Separate Address Matters
Without its own address, your ADU exists in a gray area that creates practical problems for tenants and can make the unit less attractive to quality renters. Here's what a separate address enables:
- Mail delivery: USPS, FedEx, and UPS can deliver directly
- Utility accounts: Tenants can set up electric, gas, internet in their name
- Voter registration: Tenants can register at their actual residence
- Driver's license: Can list actual address on ID
- Emergency services: 911 dispatchers can locate the unit precisely
- Legitimacy: The unit feels like a real home, not a makeshift arrangement
Common ADU Address Formats
Jurisdictions assign ADU addresses differently. Your ADU might get:
Unit Suffix (Most Common)
Main house: 123 Main Street
ADU: 123 Main Street, Unit B (or #B, or Apt B)
Simple and widely recognized. Works well with delivery services.
1/2 Address
Main house: 123 Main Street
ADU: 123 1/2 Main Street
Traditional format for secondary units. Some older systems handle this better.
Separate Street Number
Main house: 123 Main Street
ADU: 125 Main Street (or 121 Main Street)
Cleanest option but requires available numbers. Treats ADU as fully independent.
Rear or Descriptive Suffix
Main house: 123 Main Street
ADU: 123 Main Street Rear (or 123R Main Street)
Descriptive but can cause delivery confusion. Less preferred.
How to Apply for a Separate Address
Contact Your City's Addressing Department
This may be part of the planning department, building department, GIS office, or a standalone addressing coordinator. Search "[your city] address assignment" or call the main city line.
Pro tip: Some cities automatically assign addresses during the permitting process. Check if your ADU permit already includes an address.
Submit Required Documentation
Typical requirements include:
- • Address assignment application form
- • Copy of Certificate of Occupancy
- • Site plan showing ADU location on property
- • Proof of ownership (deed or tax record)
- • Filing fee ($0-100 depending on jurisdiction)
Wait for Processing
Processing times vary significantly:
- • Fast jurisdictions: 1-2 weeks
- • Average: 2-4 weeks
- • Slow jurisdictions: 4-6 weeks
The city coordinates with the post office, county assessor, and emergency services.
Install Address Numbers
Once assigned, display the address prominently:
- • Numbers at least 4 inches tall (check local code)
- • Contrasting color from background
- • Visible from the street or access point
- • Illuminated or reflective for nighttime visibility
Notify Relevant Parties
Help establish the new address in various systems:
- • Post Office: Confirm delivery will start
- • Utilities: Set up accounts or sub-meters
- • Google Maps: Add the address for directions
- • Insurance: Update your landlord policy
Setting Up Mail and Package Delivery
USPS Setup
The post office is notified during address assignment, but confirm:
- • Visit your local post office with the address assignment letter
- • Ensure the carrier knows about the new address
- • Install a separate mailbox if required (check with post office)
- • Some addresses share a mailbox with separate slots
Package Delivery (FedEx, UPS, Amazon)
Private carriers update address databases slower than USPS:
- • Add the address to Google Maps for driver navigation
- • Tenants should include clear delivery instructions
- • Consider a separate entrance or delivery area
- • Address recognition improves over time as deliveries are made
Pro tip: Adding your ADU to Google Maps helps delivery drivers find it. Go to Google Maps > Menu > Add a missing place.
Frequently Asked Questions
What if my city won't assign a separate address?
Some jurisdictions are resistant. Options include: using a unit number (123 Main St Unit B) even if not formally assigned, setting up a PO Box for the tenant, or escalating to city council if this is a common problem affecting ADU owners.
Can tenants set up utilities without a separate address?
Sometimes, but it's harder. Utility companies may accept "123 Main St Unit B" or "123 Main St Rear" even without formal assignment. Call each utility to ask about their requirements. Alternatively, you can keep utilities in your name and bill the tenant.
Does a separate address affect my property taxes?
The address itself doesn't increase taxes, but the ADU construction likely already triggered a reassessment. The county assessor may create a separate parcel number for the ADU, but this is for record-keeping, not additional taxation.
How long until the address shows up in online databases?
USPS updates quickly (1-2 weeks). Google Maps can take 1-4 weeks to approve submissions. Credit bureaus and background check databases may take 1-3 months. In the meantime, tenants can use the address with a note like "new construction" if systems don't recognize it.
Ready for the Next Step?
With your address established, it's time to set up your ADU as a rental property— registering as a landlord, drafting your lease, and preparing for tenants.