Two houses can both say "Marietta, GA" on the listing and still answer to two different utility systems. The mailing address covers a large stretch of Cobb County. The City of Marietta's limits cover much less. The line between them decides who runs your trash pickup, whether your water bill carries a stormwater fee, and which electric rate decisions reach your mailbox.
In 2026 that line also shows up on the bill. Cobb County added a new charge that stops at the city limit. Marietta Power held its rates for another year. Both water systems raised prices. On each side of the line, part of what you pay the utility helps fund local government. When you buy a house, you're also buying into one of two ways of paying for it.
On June 1, 2026, the Cobb County Water System began charging a dedicated stormwater utility fee to customers in unincorporated Cobb and the City of Mableton. The residential fee is $4.75 a month. Customers inside the city limits of Acworth, Austell, Kennesaw, Powder Springs, Marietta and Smyrna don't pay it, because the county Water System doesn't provide stormwater service in those cities.
Cobb's own wording says its water customers inside Marietta's city limits are exempt. So the fee follows the city limit line, not the water provider. Two Cobb Water customers on either side of that boundary now get different bills for the same water.
The fee is pegged to impervious surface. One "equivalent residential unit" is 3,700 square feet of roof, driveway and pavement, which the county describes as the median for single-family homes in its service area. Cobb publishes an Impervious Surface Map where owners can look up a parcel and the fee attached to it. A Stormwater Credit Manual lists steps residential and non-residential owners can take to lower it. Commissioners approved the change on November 20, 2025.
Unincorporated homeowners were already paying for stormwater before June. The cost just wasn't visible. Before June 1, 2026, the county folded stormwater into water and sewer charges, so the amount rose and fell with how much water a household used. A residential customer using 5,000 gallons a month paid about $2.34 a month toward stormwater without seeing it. When the separate fee started, the county lowered water and sewer rates to cover part of it.
You can see the trade in Cobb's own rate tables:
| Cobb Water, single-family residential | Before June 1, 2026 | Effective June 1, 2026 |
|---|---|---|
| Tier 1 water, per 1,000 gallons | $4.01 | $3.85 |
| Tier 2 water, per 1,000 gallons | $6.18 | $5.95 |
| Tier 5 water, per 1,000 gallons | $11.65 | $11.25 |
| Sewer, per 1,000 gallons | $7.79 | $7.51 |
| Stormwater | Built into the rates above | $4.75 flat monthly fee |
The new schedule doesn't stay put, either. In December 2024 the Board of Commissioners adopted 3.5 percent annual increases in water and wastewater charges for 2026 through 2029, each taking effect January 1. The next one lands about two months after this post. A buyer comparing a recent seller's bills against next year's numbers should expect that step up.
The table also shows where the money goes. Cobb notes that up to 10 percent of Water System revenue can be moved into the county's General Fund, and the transfer for FY25 was 5 percent. A water bill in unincorporated Cobb pays for more than water.
The City of Marietta uses the same mechanism on a much larger scale. Its Board of Lights and Water runs Marietta Power and Marietta Water. The Marietta Daily Journal reported that in the city's fiscal year 2026 budget, which runs July through June, the city planned to take about $15.5 million from utility revenues. That's roughly 20 percent of the general fund, the city's main operating budget.
That explains why city addresses get no separate stormwater fee. In Marietta, storm drainage is a city department job. The city's FY2027 budget assigns the Streets Division to maintain streets, sidewalks, curbs and gutters, rights-of-way and storm water collection systems throughout the city, and its crews sweep streets every six to eight weeks. The county shows the cost of stormwater as its own line on the water bill. The city pays for it out of a general budget that leans on utility revenue.
City water still got more expensive in 2026. The Marietta Daily Journal reported that the BLW board approved 2026 water and wastewater rate increases at its December 8, 2025 meeting, and City Council approved them unanimously two days later. Officials put the combined increase at about $3.05 a month for the average residential customer, starting with February bills. The city cited "rising wholesale costs" and "infrastructure pass-through charges" from the regional treatment providers, the Cobb County-Marietta Water Authority and the Cobb County Water System. Part of the city's water cost comes from the same county system that raises its rates every January.
Electric rates show the funding model most clearly. In February 2026, Marietta Power announced no planned electric rate increase for 2026. It said it had gone 12 of the last 13 years without a rate increase and ranked second lowest in the Georgia Public Service Commission's Residential Rate Survey for average home usage. Mayor Steve Tumlin, who chairs the Board of Lights and Water, said in the release that "we have absorbed wholesale cost increases to hold rates steady for our customers." A year earlier, the city reversed a planned 2.5 percent increase that had been set for late 2024.
A home outside the city may be served by a different electric company, and those companies set rates through different processes:
Which provider serves a given house depends on the parcel, not the mailing address. Ask for it by name before you compare monthly costs.
Trash is the difference a new owner runs into on the first day after closing. Cobb County says plainly that its Sustainability, Waste and Beautification Department doesn't collect trash in unincorporated Cobb. Residents hire a private company from the county's permitted hauler list, which lists 18 companies as of January 2026. The county says haulers can choose whether to serve a given resident, and it has no authority over their prices or service quality. A new owner in unincorporated Marietta has to set up trash service themselves, and the county suggests starting with the HOA or the neighbors.
Inside the city, sanitation comes with the address. The city's FY2027 budget says the Sanitation Division serves about 13,000 households with garbage collection and weekly curbside yard waste pickup. City Customer Service bills those charges to customers who live inside the city limits. Cobb lists the city's service as Marietta Environmental Services, (770) 794-5595.
| Inside the City of Marietta | Unincorporated Cobb, Marietta mailing address | |
|---|---|---|
| Stormwater | No Cobb stormwater fee; storm drains maintained by the city Streets Division | $4.75 monthly Cobb fee since June 1, 2026 |
| Water and sewer | Marietta Water raised rates for 2026; Cobb Water customers inside the city limits also skip the stormwater fee | Cobb Water, with 3.5 percent increases each January 1 through 2029 |
| Electric | Marietta Power, with no planned 2026 increase | Depends on the parcel; Georgia Power and Cobb EMC each have 2026 rate schedules |
| Trash | City sanitation, billed by the city | Private hauler chosen and paid by the owner |
| Where some utility revenue goes | About 20 percent of the city's FY2026 general fund | 5 percent of Water System revenue to the county General Fund in FY25 |
Before you make an offer on a "Marietta" home, a few checks will tell you which column you'd be living in:
Does a Marietta zip code mean the home is in the city? No. The mailing address and the city limit are two different lines. The county's jurisdiction lookup gives the answer for a specific address.
Can a Cobb Water customer avoid the stormwater fee? Cobb doesn't charge the fee to its customers inside the Marietta city limits or the other exempt cities. For unincorporated properties, the county's Stormwater Credit Manual describes the ways owners can qualify for a reduction.
Will the Cobb water rates in this post still be right next year? Not exactly. The county already adopted a 3.5 percent increase for January 1 of each year through 2029, so the June 2026 schedule is a starting point.
This post is general information, not legal, tax or financial advice, so please confirm the fees and rules for your own address directly with the utility or a qualified professional.
When we put two Marietta homes side by side for you, we check which side of the city limit each one sits on and what that means for the monthly bills, along with the price. If you'd like that comparison for the homes on your list, reach out to The Carlson Orange Team and Talk to Your Real Estate Family.
