Development impact fee
Also: impact fee, development fee
A one-time charge a local government imposes on new development to pay for the off-site capital infrastructure that growth makes necessary — roads, parks, schools, fire and police facilities, and the like. It is meant to fund expansion of public facilities, not to cover the cost of reviewing or inspecting the project itself.
System development charge (SDC)
Also: SDC, system development charge
A one-time fee a water or sewer utility charges a new connection to recover its share of the cost of the system's existing and future capacity. "SDC" is the common term in the Pacific Northwest and parts of the West; functionally it is the same idea as a capacity charge or buy-in.
Tap fee
Also: tap fees
The charge to physically connect a building to the public water or sewer main (the "tap"). In everyday use the term is often broadened to mean the whole water/sewer connection charge, including the capacity (buy-in) component, not just the physical tap.
Connection fee
Also: connection charge
A general term for the one-time fee a utility charges to add a new water or sewer service. Depending on the jurisdiction it is labeled a tap fee, capacity charge, system development charge, plant investment fee, or general facilities charge.
Capacity charge
Also: capacity fee, buy-in fee
The portion of a water or sewer connection fee that buys the new user a share of the system's treatment, pumping, and storage capacity. It is typically the largest part of a connection fee and is often scaled to the size of the water meter or to estimated demand.
Plant investment fee (PIF)
Also: PIF, plant investment fee
A water or sewer capacity charge, named for the new user's "investment" in treatment plant and system capacity. The term is common in Colorado, where PIFs (especially for water) are frequently the single largest fee on a new home.
General facilities charge (GFC)
Also: GFC, general facilities charge
Washington's standard name for a water or sewer connection capacity charge. A GFC recovers a new connection's equitable share of the cost of system facilities and is charged separately from any school or transportation impact fee.
Nexus study
Also: impact fee study, nexus analysis
The technical study that justifies an impact fee by demonstrating a reasonable relationship ("nexus") between new development, the need for new infrastructure, and the fee amount charged. Most states require a current nexus or impact-fee study before a fee can be adopted or increased.
Mitigation Fee Act (AB 1600)
Also: AB 1600, Mitigation Fee Act
California's governing law for development impact fees (Government Code §66000 et seq.), enacted by AB 1600 in 1987. It requires a city or county to identify the purpose and use of each fee and to show a reasonable nexus between the fee and the development it is charged against.
AB 602
Also: Assembly Bill 602
A 2021 California law (effective 2022) that standardized how impact-fee nexus studies are prepared and published — for example requiring fees on residential development to be expressed per square foot where feasible, and directing agencies to post current fee schedules online.
Impact Fee Facilities Plan (IFFP)
Also: IFFP, facilities plan
Under Utah's Impact Fees Act, the plan a jurisdiction must adopt identifying the existing level of service and the additional public facilities needed to serve new growth. The IFFP defines what an impact fee may fund; the companion Impact Fee Analysis sets the dollar amount.
Impact Fee Analysis (IFA)
Also: IFA, impact fee analysis
Utah's required companion document to the IFFP: the analysis that calculates the proportionate-share cost of new facilities attributable to growth and translates it into the per-unit impact fee that may be charged.
In-lieu fee
Also: fee in lieu, in lieu fee
A payment a developer makes instead of meeting a physical or dedication requirement directly — for example, paying a parkland in-lieu fee rather than dedicating land on site. The agency pools the money to provide the facility elsewhere.
Linkage fee
Also: housing linkage fee, jobs-housing linkage fee
A fee imposed on new commercial, office, or market-rate residential development that is "linked" to a need it generates — most commonly an affordable-housing or jobs-housing linkage fee that funds below-market housing or transit.
Inclusionary housing fee
Also: inclusionary in-lieu fee, affordable housing in-lieu fee
A fee paid in lieu of building required below-market-rate units under an inclusionary housing ordinance. Instead of including affordable units on site, the developer pays the fee and the jurisdiction funds affordable housing elsewhere.
School facilities fee
Also: school impact fee, school fee
A fee levied by a school district to fund classroom capacity for the students new housing will generate. In California it is charged per square foot of residential floor area, so larger homes pay more; many states (Texas, Arizona, Colorado, Utah, Idaho) do not authorize school impact fees at all.
Per dwelling unit
Also: per door, per unit
The basis on which residential impact fees are most often charged — one fee per home, regardless of square footage. ImpactFeeAtlas normalizes residential fees to a per-dwelling-unit basis so jurisdictions can be compared on the same footing.
Land use
Also: land use type, land use category
The category a project falls into for fee purposes — single-family detached, single-family attached (townhome), multifamily, ADU, mobile home, or a nonresidential type. Fee schedules set different amounts by land use because each generates different demand on infrastructure.
Accessory dwelling unit (ADU)
Also: ADU, granny flat, secondary unit
A smaller secondary home on a lot with a primary residence (a backyard cottage, basement unit, or garage conversion). Because ADUs add little net demand, many jurisdictions reduce or waive impact fees for them — in California, state law exempts ADUs under 750 square feet.
Meter size / equivalent residential unit (ERU)
Also: ERU, equivalent residential unit, meter size
Water and sewer capacity charges are commonly scaled to the size of the water meter, which is a proxy for demand. The base residential meter (typically 5/8" or 3/4") equals one equivalent residential unit (ERU); larger meters are charged a multiple of the ERU rate. ImpactFeeAtlas uses the base residential meter for comparison.
Construction cost index (CCI) escalation
Also: CCI escalation, ENR escalation, annual fee escalation
Many fee schedules automatically adjust each year by a published construction cost index (for example the ENR Construction Cost Index) so the fee keeps pace with the cost of building infrastructure. This is why a quoted fee can rise between annual updates even with no policy change.
Growth Management Act (RCW 82.02)
Also: GMA, RCW 82.02, Washington Growth Management Act
Washington's enabling law for impact fees (RCW 82.02.050 et seq.), part of the Growth Management Act. It authorizes cities and counties to collect impact fees for transportation, parks, schools, and fire facilities, and requires the fees to be spent on growth-related capacity.
Local Government Code Chapter 395 (Texas)
Also: Chapter 395, Texas Chapter 395, LGC 395
The Texas statute that governs impact fees. It limits them to four categories — water, wastewater, roadway, and drainage — and prescribes the capital improvements plan and study process. Texas does not authorize park, school, fire, police, or library impact fees.
A.R.S. §9-463.05 (Arizona system development fees)
Also: ARS 9-463.05, Arizona system development fee, SDF
Arizona's impact-fee statute, which calls the charges "development fees" (often "system development fees"). After the 2014 reform it tightened what may be charged, requires a study update roughly every five years, and excludes categories such as schools.
Florida Impact Fee Act (and HB 337)
Also: HB 337, Florida Impact Fee Act
Florida's framework authorizing local impact fees, codified in §163.31801. HB 337 (2021) added caps on how fast fees can be increased — generally a phased schedule for larger hikes and extra justification beyond defined thresholds — so Florida fees tend to step up on a set cadence rather than escalate automatically.
Building permit fee
Also: permit fee, plan review fee
A fee that covers the cost of reviewing plans and inspecting construction for code compliance — not infrastructure. It is a separate, much smaller charge than impact and connection fees, and ImpactFeeAtlas deliberately excludes it because it funds the permitting process rather than off-site capital.