Cerro Gordo County, home to Mason City and roughly 43k Iowans, uses Iowa's distinctive "rollback" system: assessed value is set at 100% of market value, but only a fraction of that value is actually subject to taxation. The fraction — the residential rollback — is set annually by the Iowa Department of Revenue to limit aggregate statewide residential taxable value growth to no more than 3% per year. For FY2026, the residential rollback is 44.5345%.
How the bill is built
Iowa's tax math has three steps and one unique constraint. Step 1: Assessed Value. The local assessor (county or city — seven Iowa cities have their own city assessors, including Davenport, Iowa City, Cedar Rapids, Sioux City, Dubuque, Ames, and Mason City) values your property at 100% of fair market value, per Iowa Code 441.21. Step 2: Taxable Value. Multiply Assessed Value by the residential rollback (44.5345% for FY2026) to get Taxable Value. The rollback is a uniform statewide percentage set annually by the IDR. Step 3: Apply the consolidated levy rate. Multiply Taxable Value by the consolidated rate (36.20 per $1,000 for Mason City) and divide by 1,000.
Then subtract credits: the Homestead Tax Credit (typically $50-150 for primary residences), the 65+ Homestead Exemption ($6,500 of taxable value, FY2026 onwards), and the Military Service Exemption ($4,000 of taxable value for wartime veterans). 100% disabled veterans receive a full property tax credit equal to their entire bill.
Cerro Gordo County rate breakdown (consolidated levy per $1,000 of Taxable Value, Mason City district)
| Taxing entity | Rate |
|---|---|
| Mason City + MC Schools + Cerro Gordo County (consol) | 36.2000 |
| Combined total | 36.2000 |
Data record updated April 25, 2026. This is an editorial update date, not a tax year or a guarantee that every figure has been independently verified.
Sources and scope: Check rates and parcel details with Cerro Gordo County Assessor. Figures may refer to different source years; a county-seat rate does not apply to every address. How we use data and estimates.
Credits and exemptions for 2026
Iowa's exemption system has two distinct mechanisms working in parallel: credits (which reduce the final tax bill in dollars) and exemptions (which reduce the taxable value before the rate is applied). Both must be filed with your local assessor (county or city) and most are one-time filings that continue automatically once granted.
Homestead Tax Credit — for primary residences
If you own and occupy Mason City as your primary residence, file Form 54-028 (Homestead Tax Credit and Exemption) with your local assessor. The Homestead Credit reduces your tax bill by an amount equal to $4,850 × your school district's portion of the consolidated rate ÷ 1,000 — typically $50 to $150 per year. Filing deadline: July 1. One-time filing; automatic renewal as long as you continue to qualify.
To qualify, you must (a) be an Iowa resident, (b) own the home, and (c) actually live in the property on July 1 and for at least 6 months of the tax year. Exceptions exist for active military and nursing home residents.
65+ Homestead Exemption — added by HF 718 (2023)
Owners aged 65 or older receive an additional $6,500 exemption from taxable value (FY2026 onwards). This is in addition to the Homestead Credit — both can be claimed by qualifying senior owners. The exemption was phased in: $3,250 for FY2025, $6,500 for FY2026 and onwards. Use the same Form 54-028.
This is an exemption (reducing taxable value before the rate is applied), not a credit (reducing the final bill). On a 36.20 per $1,000 consolidated rate, the senior exemption saves approximately $235 per year.
Disabled Veteran Homestead Tax Credit — full property tax exemption
Veterans with a 100% service-connected permanent and total disability rating from the VA — or unmarried surviving spouses of qualifying veterans — receive a credit equal to 100% of their property tax bill on their primary residence. This is a full exemption in practical terms.
File Form 54-049 (Disabled Veteran Homestead Tax Credit) with your local assessor, with VA disability rating documentation attached. One-time filing; automatic renewal as long as the veteran qualifies.
Military Service Tax Exemption
Veterans who served during a qualifying wartime period receive a $4,000 exemption from taxable value (raised from $1,852 by HF 718, effective FY2025). Available to all qualifying veterans regardless of disability status. File Form 54-146 (Military Service Tax Exemption) with your assessor by July 1.
Iowa Property Tax Credit (Elderly & Disabled, income-limited)
Owners age 70+ (and disabled owners 23+) with low household incomes can apply for the Iowa Property Tax Credit Claim (Form 54-001). Maximum credit is $1,000. Income guidelines are tied to federal poverty thresholds and updated annually. File with your county treasurer (not the assessor) between January 1 and June 1.
Appealing your assessment
Iowa's appeal process has a distinct multi-step structure. Your Assessment Roll Notice arrives in mid-April. You may first request an informal review with the assessor (deadline April 25). If unresolved, file a written protest with the Local Board of Review (deadline: between April 2 and April 30 in most counties; check with the Cerro Gordo County Assessor). Board hearings run May 1-31.
If the Board's decision is unsatisfactory, you can appeal to the Iowa Property Assessment Appeal Board (PAAB) within 20 days of the Board of Review's final adjournment (typically mid-to-late June). Alternatively, you can appeal directly to the District Court within 20 days. PAAB is generally cheaper and faster for residential appeals; District Court for commercial.
Effective appeal strategy: focus on your assessed value (the assessor's market value estimate), not the rollback or rate. Iowa requires assessment at 100% of market value — if your assessment exceeds true market value, you have a strong case. The most useful evidence is comparable sales data within 12-18 months of January 1 of the assessment year.