Fort Collins Homes Outside City Limits: East Mulberry Annexation

"Colorado, including Unincorporated Larimer County, is a buyer beware market." That's the language Larimer County itself uses to describe what happens when a property sits outside city limits, and it applies to a surprising number of addresses that read Fort Collins on the listing sheet.

Most buyers assume that if a house sits inside the ring of Fort Collins streets, shopping, and city services, it belongs to the city. For a real but shrinking set of parcels along the East Mulberry corridor, that assumption is wrong. These properties are surrounded on nearly every side by Fort Collins city limits and still governed by Larimer County. The house looks like Fort Collins. The mail comes to a Fort Collins address. But the taxing authority, the patrol agency, and in some cases the sewer connection all answer to the county, not the city, until an annexation ordinance says otherwise.

What Buyer Beware Actually Means Here

In most of Fort Collins, a home inspection, an appraisal, and a title search work together to surface problems before closing. In unincorporated Larimer County, that safety net has a hole in it. Larimer County Code Compliance says Colorado law does not require a realtor, lender, home inspector, appraiser, or title company to research whether a property has zoning or building code violations. If a problem shows up after the sale, it becomes the new owner's problem to fix, and any dispute over who should have caught it plays out between buyer and seller after the fact.

Larimer County's Code Compliance team will run a free property research report on request, checking building approvals and land use history for a specific parcel in the unincorporated county. It's a useful step precisely because nothing else in a standard transaction is designed to catch what that report catches.

The Pocket Fort Collins Didn't Draw On Purpose

The East Mulberry Enclave exists because the city grew around it rather than through it. As Fort Collins annexed development along the Mulberry corridor over the years, it eventually surrounded a cluster of properties that were never brought into the city themselves. By 2018, that cluster was fully encircled by city limits, officially forming the enclave. According to Fort Collins' East Mulberry annexation information, three years of being surrounded made those properties eligible for involuntary annexation under Fort Collins' agreement with the county, but eligible is not the same as annexed.

The city's updated East Mulberry Plan, adopted in December 2023, replaced any fixed annexation timeline with a threshold system instead. Rather than scheduling the enclave for annexation on a set date, the city watches for specific conditions, service capacity, infrastructure readiness, and property owner interest, and brings parcels in as those thresholds are met. That means two lots a few hundred feet apart can be on completely different sides of the city line for years, with no calendar telling either owner when that changes.

Here's what actually shifts once a property crosses from county to city:

The sales tax shift is not abstract. Fort Collins' sales tax FAQs explain that the city is a home rule municipality that administers its own sales and use tax separately from the state and county. Once a home is annexed, the owner becomes subject to city tax on top of whatever state and county tax already applied.

The wastewater question matters just as much at the inspection table. Larimer County's Health and Environment Department regulates on-site septic systems under state Regulation 43, and pre-purchase septic inspections are worth requesting specifically because they produce a written report suited to a real estate transaction. Repairs run from a few hundred dollars for a minor fix to $3,000 to $10,000 or more for drain field work, and a full tank replacement typically falls between $4,000 and $8,000. If city sewer has since been extended to the street through Fort Collins Utilities or another local water district, converting from septic to sewer is possible, but it means a new sewer line.

Watching One Parcel Cross the Line

The clearest evidence that this enclave is a living, moving boundary rather than a historical footnote is happening right now. In 2026, the city advanced the Peakview Annexation No. 2, a roughly 70-acre voluntary annexation at the northeast corner of Greenfields Drive and East Mulberry Street. The parcel combines the Cooper Slough Hunting Club property with several lots from the Parkview development plat recorded in the county back in 2022, and it sits directly adjacent to Bloom, the mixed-use development already inside city limits. BizWest reported on the plan advancing in May 2026, and the Planning and Zoning Commission held its public hearing on April 16, 2026, recommending approval before it moved to City Council for first reading.

What stands out is how quiet the process has been on the ground. A neighborhood meeting was held back in September 2022, and no members of the public attended. That's not unusual for annexations in this corridor. Owners and developers often initiate these voluntary petitions themselves, years before a buyer ever sees the listing, which means a property can be mid-annexation without a casual search turning up anything obvious.

The Cooper Slough drainage way runs through the site, and the existing plat already preserves a wetland and wildlife buffer along with a trail corridor and stormwater infrastructure that carries forward once the land is annexed. None of that changes because of the paperwork. What changes is who taxes the property, who patrols it, and who enforces its building code going forward.

What to Check Before You Write an Offer

For a buyer comparing two homes that both say Fort Collins, a few extra questions can save a lot of confusion later.

1. Confirm the property's actual jurisdiction using Larimer County's online zoning map, which lets you search a specific address and turn on the zoning districts layer to see whether it falls inside city limits or the unincorporated county.
2. Ask directly whether the home is on septic or city sewer, and if it's on septic, request a current inspection report written for a real estate transaction rather than a routine service visit.
3. If the property sits in the East Mulberry area specifically, ask whether it's part of the enclave and whether any annexation petition is pending, since that history is public record through the city's planning department.
4. Note which agency would respond to a call at that address. In the unincorporated county, that's the Larimer County Sheriff's Office. Inside city limits, it's Fort Collins Police Services. Neither is better or worse, but knowing which one applies avoids confusion later.
5. If the home has been annexed recently or might be soon, ask your lender or closing agent whether that affects any tax proration or future permit costs tied to renovations you're already planning.

A Couple of Questions Worth Asking Directly

Does every property near East Mulberry sit in the enclave? No. Much of the corridor has already been annexed over the years as individual owners petitioned the city voluntarily. The enclave refers specifically to the parcels that remain unincorporated, and that footprint shrinks a little every time a petition like Peakview Annexation No. 2 goes through.

If I buy a home in the enclave, will it eventually be annexed automatically? Not on a set schedule. The city's threshold approach means annexation happens when conditions like infrastructure capacity and development activity line up, not on a fixed date. A property could remain in the county for years, or move through the process much faster if a voluntary petition is already underway.

Buying in or near a corridor like this isn't a reason for concern. It's a reason to ask a specific, local question before you write an offer instead of after you've closed. If you're comparing listings around Fort Collins and want to know exactly what jurisdiction a specific address falls under before you get attached to it, Catherine Montgomery can pull that answer alongside the rest of your search.

This article is general information, not legal, tax or financial advice. Consult a qualified professional about your situation.