Fullerton ADU Market Update — May 2026: What the Latest Comps Tell Investors and Sellers
If you've been watching the Fullerton ADU market and wondering whether the numbers still work, the answer coming out of this spring is yes — but it depends heavily on which part of Fullerton you're looking at and what you're trying to accomplish.
This update is based on the active, pending, and recently closed MLS data pulled in May 2026. Here's what the market actually looks like right now.
The Big Picture: A Tale of Two Fullerton Markets
Fullerton splits cleanly into two distinct ADU submarkets, and lumping them together gets investors into trouble.
North Fullerton (92835) — think Sunny Hills Estates, Green Acres, and the Laguna Lake corridor — is a luxury estate market. Properties here sit on large lots (half an acre to over an acre), were built in the late 1950s through 1960s, and have been updated into premium homes. ADUs in this pocket are detached guest houses, casitas, and studio units built into the property's footprint. Prices run $2.6M to $3.3M. This is not a pure cash-flow play — it's a lifestyle purchase with an income kicker.
Central and South Fullerton (92831/92833) — near Cal State Fullerton, Downtown Fullerton, and along the Euclid corridor — is where the investor-grade ADU activity lives. Entry prices run $1.29M to $1.45M, ADU footprints are purpose-built for rental income, and the tenant pool is deep thanks to CSUF, the medical corridor near St. Jude, and easy freeway access. This is where the cash-flow math works for buyers who need the numbers to pencil.
Active Listings: What's on the Market Right Now
There are three active ADU properties in Fullerton as of mid-May 2026. All three are in the North Fullerton luxury pocket, and two have already seen price reductions.
520 W Hermosa Drive — $2,650,000 — A 2,928 sq ft custom home on a 0.59-acre elevated lot in Sunny Hills Estates near Laguna Lake. The ADU is a private studio (370 sq ft) with its own entrance, kitchenette, bathroom, and laundry hookups — tastefully done and genuinely private. The property also carries resort-style outdoor amenities including a remodeled pool with Baja shelf and a fully equipped cabana with outdoor kitchen and private bath. Listed fresh on 05/11/26.
2830 Anacapa Place — $2,995,000 (reduced from $3,200,000) — One of the more flexible properties on the market right now. The main residence is 3,895 sq ft on a 23,400 sq ft lot, but the real story is the two detached casitas — one at 660 sq ft and one at 551 sq ft, each with a full kitchen, bath, and separate access. That's three units on one lot near Laguna Lake Park, with pool, spa, and RV access. The seller dropped $205,000 off the ask in May. Under California state ADU law, a single-family lot can support up to two ADUs — this property maxes that out.
1419 N Richman Knoll — $3,299,000 (reduced from $3,500,000) — A sprawling equestrian estate on 1.15 acres in the Green Acres community, with two detached ADUs: a 592 sq ft unit with full kitchen and a 371 sq ft studio. The main house is 3,389 sq ft. Direct trail access to the Fullerton Loop. The seller has taken $201,000 off the ask since January. 130 days on market.
What the actives tell you: The luxury tier is negotiating. Two out of three active properties have had significant price cuts and are sitting. If you're a buyer with the financial profile to absorb a $3M+ purchase, there's room to move on price right now.
Pending: What Just Went Under Contract
959 Rodeo Road — $3,000,000 — A 5,270 sq ft home on a 0.66-acre lot with a 700 sq ft detached ADU perched above a three-car garage. The ADU is positioned as a guest home. This one went pending on 05/03/26 after just 13 days on market — notably faster than the luxury listings above. No pool, but a custom gazebo with a built-in outdoor kitchen, TV, and speaker system, plus an 875 sq ft private gym. The relatively quick contract suggests the $3M buyer pool responds faster to properties that deliver usable square footage at a reasonable price per foot.
Closed Sales: What the Market Actually Paid
This is where the real signal lives.
660 Green Acre Drive — Closed $2,625,000 — Listed at $2,390,000, sold for $235,000 over asking in just 3 days. The property is a 3,059 sq ft single-story home on a 0.48-acre lot in Green Acres with a permitted 586 sq ft detached ADU (built 2019, separate address). Conventional financing. The over-asking sale in 3 days tells a clear story: permitted, detached ADUs on well-maintained North Fullerton lots create real buyer competition. The permitted ADU status matters — Fannie Mae's ADU income guidelines allow lenders to count rental income when qualifying buyers, which expands the buyer pool meaningfully.
128 S Citrus Avenue — Closed $1,400,000 — This is the deal investors should study. A brand-new 4-bedroom/2-bath detached ADU (1,196 sq ft, completed 2026) paired with a fully remodeled 3-bedroom/2-bath main residence (1,235 sq ft). Both units have separate meters for water, gas, and electricity. The main home was rented at $3,650/month. Estimated market rent for the ADU: $4,000/month. Combined gross income: $7,650/month. Closed conventional in 18 days. At $1,400,000, that's a gross rent multiplier of roughly 15.3x — which is solid for North Orange County. This is exactly the type of purpose-built, two-unit investment that the 2026 HCD ADU Handbook was designed to encourage.
151 N Lincoln Avenue — Closed $1,290,000 — A duplex in Fullerton's Historic Preservation Zone near Cal State Fullerton and Downtown. Two fully detached homes on a single R2P lot — the front Craftsman (1,093 sq ft, 2bd/2ba, remodeled 2022) and a rear residence functioning as a 1,095 sq ft ADU (2bd/2ba, separate address, separate meters). Closed with FHA financing in 17 days. Separate gas and electric meters made FHA qualification cleaner. Buyers in the CSUF corridor are active, and the relatively short DOM confirms that.
139 Ramona Drive — Closed $1,343,000 — A 1,915 sq ft home with an ADU-style lower-level mother-in-law suite with its own private entrance, bedroom, kitchen area, and bathroom. Cash buyer. 119 days on market with a price drop from the original $1,399,000. The long DOM and deep discount (original ask to close: $56,000) suggest buyers discount attached, lower-level ADUs more heavily than detached units — especially when the ADU lacks separate meters.
What the Numbers Tell You
Pulling back across all the comps, a few patterns are clear:
Detached > attached, always. The gap between 660 Green Acre (sold over asking, detached permitted ADU) and 139 Ramona (sold under asking after 119 days, attached ADU) illustrates the premium buyers and appraisers assign to detached units with separate access.
Permits matter. The Green Acres sale and the Citrus Avenue deal both featured permitted ADUs. Unpermitted or murky ADUs create appraisal problems, complicate financing, and shrink the buyer pool. The City of Fullerton's ADU program waives permit fees for ADUs under 750 sq ft — there's no financial reason to skip the permit process on smaller units.
Separate meters close faster. The two fastest closings in this dataset — 128 S Citrus (18 days) and 151 N Lincoln (17 days) — both had separate utility meters. Separate meters allow FHA and conventional lenders to treat the ADU income more cleanly, and they give buyers confidence that the rental unit truly operates independently.
Luxury is negotiating, entry-level is moving. The $1.29M–$1.45M range is closing in 17–18 days. The $2.65M–$3.3M range is sitting with price cuts. If you're a seller in North Fullerton with a luxury estate, price it right in the first 30 days or you'll be chasing the market down.
The Rental Income Picture
Fullerton's broader apartment market averages around $2,528/month as of spring 2026. ADUs — especially new or well-finished detached units — consistently exceed that. The Citrus Avenue ADU was estimated at $4,000/month for a brand-new 4bd/2ba unit with an attached garage, and a 1,200 sq ft 3-bedroom ADU on Oak Street was listed at $3,900/month. Smaller studio and one-bedroom ADUs in Fullerton run $2,450–$2,800/month depending on finish level and location.
The tenant demand is structural. Cal State Fullerton enrolls over 40,000 students. St. Jude Medical Center is a major employment anchor. And Fullerton's freeway access — the 57, 91, and 5 — keeps it in range for LA County commuters. Unlike thinner ADU markets like Cypress or Buena Park where the tenant pool is narrower, Fullerton draws renters from multiple directions, which keeps vacancy risk lower.
Fullerton ADU Rules: A Quick Recap
Under California state law — which Fullerton's local ordinance aligns with — a single-family property can have up to two ADUs (one standard, one junior). The 2830 Anacapa and 1419 Richman Knoll listings are good real-world examples of what that looks like. Key parameters for Fullerton:
Detached ADUs up to 1,200 sq ft
Junior ADUs (JADUs) up to 500 sq ft within the existing home footprint
No permit fees for ADUs under 750 sq ft
No additional parking required if within a half-mile of a transit stop
Architectural design must be visually compatible with the primary dwelling when visible from the street
The city's ADU page has the full current requirements, and it's worth verifying specific setback and height rules for your parcel before you start planning.
Who Should Be Paying Attention
Sellers with permitted, detached ADUs in the $1.3M–$1.6M range — the market is absorbing these properties quickly. Price it with confidence, lead with the rental income story, and make sure your ADU's permit history is clean and documented.
Investors hunting cash flow — the $1.29M–$1.4M Central/South Fullerton deals are where the income math works. Look for properties with separate meters, permitted ADUs, and CSUF or medical corridor proximity. The Citrus Avenue deal at $1.4M generating $7,650/month gross is a template worth chasing.
Luxury buyers in 92835 — there's opportunity to negotiate right now. Two of the three active listings have already dropped by $200K+. If you're a qualified buyer who wants a large-lot estate with an income unit in one of North OC's most established neighborhoods, the window for leverage is open.
Dylan Serna is an ADU specialist agent at eXp Realty serving Orange County and LA County. DRE# 02217359. Data sourced from CRMLS, May 2026. All square footage and financial figures are approximate; buyers should independently verify.
