# Boise Raises 62.1% of Its General Fund From Property Tax. Its Levy Rate Just Fell and the Bill Still Went Up

Boise's FY2027 proposed budget takes $216,007,833 of property tax into a $347,821,431 general fund. Parker, Colorado takes 4.4%. The cap explains the gap.

Author: J.A. Watte
Published: August 20, 2026
Source: https://jwatte.com/blog/boise-property-tax-three-percent-cap/

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The City of Boise proposes to raise $216,007,833 in general fund property tax revenue for fiscal year 2027 against a general fund of $347,821,431. That is 62.1% of the fund, and both figures are proposed, not adopted. Idaho cities run 1 October to 30 September, so the FY2027 budget was still a proposal when the appropriation ordinance went onto the 11 August 2026 reading calendar.

Now put that next to Parker, Colorado. Parker budgeted $3,802,915 of general property tax into $86,586,741 of general fund revenue for 2026, adopted basis. That is 4.4%. Parker runs on sales tax, which the town itself puts at 69.7% of general fund revenue. Boise runs on property tax.

These are not two degrees of the same municipal model. They are two different machines. A Boise resident who wants to know what the city costs looks at an assessment notice. A Parker resident looks at receipts. Everything downstream, including how a council can respond to inflation and how fast a bill can move, follows from that split.

## Idaho caps the budget, not the rate

Idaho Code 63-802 limits what a taxing district may certify. The statute lets a district take the highest dollar amount of property taxes it certified in any one of the three preceding tax years, "increased by a growth factor of not to exceed three percent (3%)". On top of that, and outside the cap, a district may add the value on the new construction roll and 90% of the value of annexation from the previous calendar year.

Read that again, because the object of the cap is a dollar amount. The statute never mentions a rate. A district decides how many dollars it needs, the county divides those dollars across the taxable value in the district, and the levy rate is the quotient. The rate is an output.

Boise took less than it could have. The FY2027 proposed budget carries a 2.7% base increase against a 3.0% statutory maximum. For FY2026, adopted, the city took the full 3.0% and then drew an additional 1.0% from accumulated forgone authority, worth $2,021,390, for 4.0% of base growth before new construction was counted. FY2027 adds no new forgone draw.

Forgone authority is the other half of the mechanism. When an Idaho city takes less than the 3% it is allowed, the unused capacity does not evaporate. The city may reserve it and pull it forward later, capped at 1.0% of the annual ongoing amount. Boise did exactly that in FY2026. The cap is therefore not a ceiling on any single year so much as a ceiling on the long-run average, with a bank attached.

## Why the levy rate fell while the bill rose

This is the single most misunderstood thing about Idaho property tax, so here is the arithmetic in full, all of it from the city's own property tax analysis table, which is labelled ESTIMATED and covers the city levy only.

| Item | FY2026 | FY2027 proposed | Change |
|---|---|---|---|
| Average Boise home, assessed value | $534,250 | $545,559 | +2.1% |
| Homeowner's exemption | $125,000 | $125,000 | none |
| Taxable value after exemption | $409,250 | $420,559 | +2.8% |
| City of Boise levy rate | 0.003922679 | 0.003839523 | -2.1% |
| City portion of the bill | $1,605.36 | $1,614.75 | +$9.39 |

The rate fell about 2.1%. The assessed value of the average home rose about 2.1%. Those two roughly cancel. What does not cancel is the exemption. Idaho's homeowner's exemption is a fixed $125,000, so when market value rises, the taxable remainder rises faster than the market value did: 2.8% against 2.1%. That gap is the $9.39.

So the levy rate is a genuinely lower rate, the city is genuinely taking less than its statutory maximum, and the bill still went up. Nobody is lying. The rate is just not the thing being controlled.

Two caveats travel with that table. The city's own revenue manual states the FY2027 rate as falling "from 0.00392 to 0.003844", while the property tax analysis gives 0.003839523 for the same 2.7% scenario. Both are in the same proposed budget document. The difference is about 0.12% and I have used the analysis table value. And the city's estimate excludes the state Homeowner's Property Tax Relief Program credit.

## Police and fire: use 50.9%, not 54.9%

Boise's FY2027 proposed budget publishes police at 28.0% and fire at 22.9% of general fund department expenditures. That is 50.9% combined, on the city's own basis, and it is the number to use.

You can derive a different number, and it is arithmetically correct, which is why it needs explaining rather than ignoring. The printed police line is $105,117,980 and fire is $85,672,244, summing to $190,790,224. Divide that by the printed general fund total of $347,821,431 and you get 54.9%. The problem is the denominator. That $347.8 million total is stated net of an Intergovernmental line carrying a negative $27,077,168, a citywide cost allocation credit rather than a department. Add it back and the gross departmental base is $374,898,599, which is 7.8% larger. Every department's share is inflated by that same 7.8% relative if you use the net figure, which is why the city's own expenditure summary is footnoted "Does not include Intergovernmental" and prints 28.0% and 22.9%.

The share is also flat. On the gross basis the police and fire combined share ran 50.4% for FY2025 adopted, 50.3% for FY2026 adopted, and 50.9% for FY2027 proposed. Police grew 3.6% and fire 2.1% in the FY2027 proposal, both below the 4.9% growth in the general fund total. Sworn staffing is proposed flat at 323.00 for police and 283.00 for fire. Public safety in Boise is the baseline, not the growth driver.

## Health insurance, and why the basis decides the headline

The city's health insurance internal service fund was $26,222,700 adopted for FY2025 and is $34,256,880 proposed for FY2027. That is +30.6%, adopted to adopted, and it is the number that will get quoted.

It is also the number most likely to mislead. FY2025 actual spending in that fund came in at $31,283,633, roughly $5.06 million above the FY2025 appropriation. Measured actual to proposed, the two year rise is 9.5%. Measured adopted FY2026 ($33,181,260) to proposed FY2027, it is 3.2%.

All three are true. The 30.6% is real budget line growth off a baseline that turned out to be too low, not a 30.6% rise in what the city spends on employee medical. State the basis in the same sentence as the number or do not use it.

## The pension picture is small, and the reason is structural

Boise is in the PERSI Base Plan, a cost sharing multiple employer plan, so it runs no pension plan of its own. Employer contribution rates are 11.96% of covered payroll for general members and 13.98% for the police and firefighter class, both effective 1 April 2025 and unchanged into the FY2027 proposal.

Those rates are identical for every Idaho city, because every Idaho city is in the same plan. Twin Falls pays 11.96% and 13.98%. So does Boise. There is no municipal rate negotiation and no city specific funded ratio to compare, which removes an entire category of local budget variation that exists in Colorado.

Boise books a $142,718 thousand proportionate share of the PERSI Base Plan net pension liability at a 30 June 2024 measurement date, from its FY2024 audited financial report. Against that it holds a $91,572 thousand proportionate share of a net pension asset in the closed, overfunded Firefighter Retirement Fund, netting to roughly $51 million. Both figures are FY2024 vintage.

Total other post employment benefit liability is $12,200 thousand, measured 30 September 2024. That is small for a city of this size and the reason is in the plan description: the retiree benefit is a $10,000 life insurance policy with the premium paid by the city, plus $100 a month toward a pre-65 retiree health plan and $50 a month post-65. There is no open ended retiree medical promise, so there is no healthcare trend rate compounding inside the liability. The pressure is on active employee medical, which is the health insurance fund above.

## What the homeowner actually pays

The city levy is not the bill. Boise's own analysis puts total property taxes on the average $545,559 home at $3,852 across all districts, with the city at 42.6% of the total levy, below the 50.0% average across the Idaho cities the city studied. The $1,614.75 city portion is 41.9% of that $3,852. County, school, highway and other districts take the rest, each under its own 3% cap.

For scale: 2,178.65 total authorized FTE proposed for FY2027, up from 2,140.75 adopted for FY2026 and 2,112.00 adopted for FY2025, serving a city the budget puts at 256,450 residents on a 2026 COMPASS estimate.

## Fact-check notes and sources

- **City of Boise FY 2027 Proposed Budget** (226 pages, cityofboise.org). Source for the general fund total, the $216,007,833 property tax revenue, the 2.7% base increase, the levy rates, the homeowner impact table, the department percentages, the health insurance fund, FTE, and population. **Every FY2027 figure in this post is PROPOSED, not adopted.** The appropriation ordinance was placed on the 11 August 2026 reading calendar; the figures the council finally adopts may differ.
- **City of Boise FY 2026 Adopted Budget** and **FY 2025 Adopted Budget**. Source for the adopted comparatives, the 3.0% plus 1.0% forgone FY2026 increase, the $2,021,390 forgone draw, and the FY2025 adopted health insurance figure.
- **City of Boise Annual Comprehensive Financial Report, fiscal year ended 30 September 2024** (audited). Source for the PERSI plan description, the $142,718 thousand net pension liability share, the $91,572 thousand Firefighter Retirement Fund net pension asset, and the $12,200 thousand total OPEB liability. These are FY2024 vintage. The FY2025 report is published only through a third party viewer and its figures are not reflected here.
- **Idaho Code 63-802**, for the 3% cap and the new construction and 90% of annexation allowances.
- **PERSI contribution rate history**, for the 11.96% and 13.98% employer rates effective 1 April 2025. A city report covering FY2024 shows 14.65% for police and fire; that rate applied from 1 July 2024 and was reduced to 13.98% on 1 April 2025. Do not quote the older figure as current.
- **Town of Parker, Colorado 2026 Adopted Budget**, for the $3,802,915 property tax and $86,586,741 general fund revenue used in the 4.4% comparison. Parker's fiscal year is the calendar year and those figures are adopted.
- On the police and fire share: **50.9% is the city's published basis**. A 54.9% figure is derivable but divides by a general fund total reduced by a negative $27,077,168 intergovernmental cost allocation, inflating every department's share by about 7.8% relative. Two figures not published anywhere: the cumulative balance of Boise's banked forgone authority, and the per district breakdown behind the $3,852 total bill.

## Related reading

- **[Two States, Two Budgets, One Very Different Bill](/blog/colorado-idaho-state-budgets-taxpayer/)**: the Colorado and Idaho state general funds side by side, including the Medicaid share and the pension systems behind both.
- **[City Budgets and Public Safety in Colorado and Idaho](/blog/colorado-idaho-city-budgets-public-safety/)**: what happens to a general fund when police and fire are half of it, and why the denominators are not comparable across states.
- **[Colorado and Idaho Local Taxes](/infographics/co-id-local-taxes/)**: the levy stacks, the sales tax reliance, and where the money is actually raised.
- **[The Public Money Programs Index](/blog/public-money-programs-index/)**: a running index of the programs and budgets covered on this site.

*This post is informational, not legal, financial or municipal advisory advice. Budget figures are appropriations as adopted or proposed and change through the year. Mentions of named municipalities, districts and retirement systems are nominative fair use. No affiliation is implied.*


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