Which Parts of Sienna Are in Missouri City? The 2023 Annexation and the Rest of the Map

Is Sienna in Missouri City?

In its mailing address, yes; in its city limits, only in parts. The developer describes Sienna as a community in Missouri City, and homes across it carry Missouri City addresses. But most of Sienna lies in Missouri City's extraterritorial jurisdiction, land just outside a city's limits that the city may later annex but does not tax. Every Sienna utility district's notice to purchasers says it lies wholly or partly in that jurisdiction, and so does the levee district's.

Inside the city limits, a home pays Missouri City's tax, $0.570825 on each $100 of value for 2025, and gets the city's police, streets and code enforcement. Outside them, a home pays no city tax, and its water, sewer and drainage come from its utility district.

What did the 2023 annexation change?

It moved the whole of Sienna MUD 2 inside the city. The city annexed the district's land on August 21, 2023, and its council approved the annexation by a vote of 5 to 2 after several public hearings. The city says its authority came from the strategic partnership agreement it signed with MUD 2 in 2001, which always contemplated annexation. The annexed land is made up of sections of Sienna Steep Bank Village, the Village of Shipman's Landing and the Village of Waters Lake, and the city estimated it would add about 6,000 residents.

The district itself was dissolved on December 19, 2023, and its water, sewer, drainage and trash services passed to the city. MUD 2 levied no tax for 2023. The city put those properties on its tax roll for 2024, with the first city tax payment due January 31, 2025, so a bill there now shows the city where it used to show MUD 2.

Which other parts of Sienna are inside the city?

Pieces of three utility districts, by their own descriptions. MUD 10 says about 40 of its roughly 977 acres are inside the city's corporate limits, MUD 12 says about 115.5 of its roughly 1,096 acres are, and MUD 3 says a small portion is. MUD 4 lies wholly in the extraterritorial jurisdiction. The notices for MUDs 10 and 12 add that property in both the city and the district is taxed by both.

The Sienna Management District, a separate district covering about 370 acres within Sienna, says about 345 of them lie inside the city. The tax table that HAR, the Houston Association of Realtors, publishes for Sienna Acreage Estates also lists Missouri City among its taxing units, so an acreage lot is worth checking on its own account.

Will Missouri City annex more of Sienna?

This page found no published plan to, and the districts' own paperwork keeps the question open. Each of MUDs 3, 4, 6, 7, 10 and 12 states on its notice to purchasers that it has a strategic partnership agreement with Missouri City, which may set the timeframe, process and procedures for annexing the part of the district in Missouri City's extraterritorial jurisdiction. The same notices say Texas law governs whether a district the city annexes is dissolved, as MUD 2 was.

What annexation meant for MUD 2 is on the record: a city tax in place of the district tax, city services in place of the district's, and, the city said, no separate fire fee on the utility bill.

Who provides fire protection outside the city limits?

Missouri City, arranged through Sienna's regional utility district. Sienna Regional MUD describes itself as the coordinating district for water, wastewater, major storm drainage and fire protection from the City of Missouri City for the utility districts inside Sienna. Before the annexation, the city told MUD 2 residents they would receive fire service without a separate fee as they had then, and its question-and-answer page says annexed homeowners would see their monthly utility bill fall by the fire services fee.

The city also told MUD 2 residents that annexation put them in its Community Rating System program, which may make them eligible for a 15% discount on flood insurance premiums.

How do you check whether a Sienna house is inside Missouri City?

Read the list of taxing units on the parcel's record with the Fort Bend Central Appraisal District. A lot inside the city lists the City of Missouri City; a lot in the extraterritorial jurisdiction does not. The notice to purchasers for the lot's utility district, which the seller provides, says whether that district lies partly inside the city, and the levee district's notice covers every lot inside the levee district.

The mailing address does not settle it: a home in the extraterritorial jurisdiction and a home in the annexed sections can both be addressed to Missouri City.

What is still unknown about the city line?

Where the city line runs through a particular section of MUD 3, 10 or 12, or whether a given acreage lot is inside it; the parcel account answers that. It also cannot say whether or when the city will annex more of Sienna, what each district's partnership agreement says in full, or what the fire services fee is on a given bill, because this page has not read those agreements or a current bill.