Redmond, Washington is one of the friendlier Eastside cities for renting out an accessory dwelling unit. Under the Redmond Zoning Code, RZC 21.04.1110, every residential lot may have two ADUs or tiny homes. An ADU can be attached to the main house or built as a detached backyard cottage, its size is capped at 1,000 square feet, and there is no owner occupancy requirement. That means you can live in the main house and rent the ADU, rent both, or rent the ADU while the main house sits between uses. One important caveat: Redmond updated its ADU ordinance in mid-2026, through Ordinance 3261 adopted June 2, 2026 and still pending codification, so owners should confirm current requirements with the city's planning department before building or converting.
The short version: Redmond allows two ADUs or tiny homes per residential lot, attached or detached, with a maximum size of 1,000 square feet and no requirement that the owner live on the property. Long term rental of an ADU is allowed. Once a tenant moves in, Washington State's Residential Landlord-Tenant Act, RCW 59.18, and Redmond's local tenant protections in RMC 9.54 apply to the ADU tenancy in full.
The ADU rules live in the Redmond Zoning Code at RZC 21.04.1110. As of August 2026, the operative provisions for an owner are:
About that mid-2026 update: Ordinance 3261 amended RZC 21.04.1110 as part of a larger zoning package aligning Redmond with Washington State housing law. The ordinance text keeps the two-unit allowance, the 1,000 square foot cap, and attached or detached siting unchanged, but the amendment has not yet been folded into the published code. Before you commit money to a build or conversion, confirm the current requirements with Redmond's planning department.
Redmond's rules did not appear in a vacuum. Washington State's 2023 ADU law, House Bill 1337, now codified at RCW 36.70A.680 and RCW 36.70A.681, set a statewide floor for cities inside urban growth areas. Cities must allow at least two ADUs per lot where single-family homes are allowed, must permit detached units, may not require the owner to live on the property, and may not cap ADU size below 1,000 square feet.
That framework is why ADU rules now look similar across the Eastside. Kirkland runs a comparable program, which we covered in our guide to ADU and DADU rentals in Kirkland, and Redmond's standards sit right at the state floor: two units, 1,000 square feet, no owner occupancy condition.
For owners, the practical effect is more usable lot, more housing, and a legal way to add rental income that can help with the mortgage. The state law expressly leaves one lever with cities, though: they may still restrict using ADUs as short term rentals, and Redmond does regulate that, as covered below.
An ADU tenancy is a full tenancy. The Residential Landlord-Tenant Act applies to the ADU exactly as it would to a house, which means the ADU needs its own written lease, its own deposit accounting, and its own notices. On top of the state layer, Redmond adds its local tenant protections chapter, RMC 9.54, in effect since 2022:
If you are setting up your first rental in the city, our guide to renting out your home in Redmond walks through the whole compliance stack in detail.
Renting both the main house and the ADU puts two separate tenancies on one lot, and that is where most self-managing owners get into trouble. The mechanics matter:
The takeaway: one lot, two tenancies, two complete sets of paperwork. The shared-lot details you settle in the lease are the ones that never turn into disputes later.
Only with a city business license. Under RMC 5.04.130, long term rentals of four or fewer units at one location are exempt from Redmond's business license requirement, but any short term rental requires a license, regardless of size, and Redmond tightened its short term rental rules effective January 1, 2026. State law backs the city up here: RCW 36.70A.680 expressly allows cities to restrict the use of ADUs as short term rentals.
Our focus at Sagareus Property Management is long term tenancy, which is also where the ADU math tends to be steadiest: continuous occupancy, one set of rules, and none of the licensing overhead.
Usually, with a notable exemption. Washington State's 2025 rent stabilization law, RCW 59.18.700, limits rent increases for covered tenancies to 7 percent plus inflation or 10 percent, whichever is less, and bars any increase during the first 12 months of a tenancy. The Washington State Department of Commerce publishes the exact ceiling each year; for 2026 it is 9.683 percent.
The nuance for ADU owners sits in the exemptions at RCW 59.18.710. A tenancy in a single-family owner-occupied residence, where the owner rents out no more than two units or bedrooms, expressly including an attached or detached ADU, is exempt from the cap. Live in the main house and rent the ADU, and the cap generally does not limit your increase. Two things narrow that exemption: it does not apply when the owner is a corporation, a REIT, or an LLC with a corporate member, and it disappears if you move out and rent both units. A separate exemption covers units whose first certificate of occupancy is 12 or fewer years old, which can reach a newly built ADU. Exempt or not, every increase still needs proper written notice, including Redmond's 120 and 180 day tiers. This is information, not legal advice; how the exemptions apply to your ownership structure is worth confirming before you rely on one.
Two. Under RZC 21.04.1110, two ADUs or tiny homes are allowed on each residential lot in Redmond, Washington, attached to the primary home or detached, with each ADU capped at 1,000 square feet. Redmond amended the ordinance in mid-2026, so confirm current requirements with the city's planning department before building.
No. Redmond has no owner occupancy requirement for long term ADU rentals, consistent with Washington State law, RCW 36.70A.681, which bars cities from imposing one. Note that where you live still affects the state rent cap: the owner-occupied exemption in RCW 59.18.710 only applies while you live on the property.
Not for a long term rental; RMC 5.04.130 exempts long term rentals of four or fewer units at one location. Any short term rental requires a Redmond business license regardless of size, under rules the city tightened effective January 1, 2026.
A vacant home is won or lost on speed and presentation, so we treat both as disciplines, not hopes. Every day a unit sits empty is income the owner never gets back, and the listing that responds first and looks best is the one that fills. Here is how we run it:
You set the goal, whether that leans toward top rent or fastest occupancy. We bring the market read, run the system, and report the numbers every week until the lease is signed.
Speed and presentation are not luck. They are how we shorten your vacancy.
An ADU is a small unit with a full-size compliance stack, and leasing it well is the same discipline as leasing a house. Sagareus Property Management manages main-house-plus-ADU properties across the Eastside, including full Redmond property management. Curious what professional management would cost for your ADU or your whole property? Our instant calculator gives you a real range in under a minute, no email required. Request your instant estimate.