Impact Fee Calculator

No -- they're illustrative starting points meant to show how the categories combine, not any specific jurisdiction's real fee schedule. Impact fees vary dramatically from one city or county to the next, even between neighboring jurisdictions, because each one sets its own schedule through its own nexus study and state enabling statute. Always replace every per-unit fee with your local jurisdiction's current published schedule before relying on the totals.

Total per Unit sums the six category fees (Transportation, Water, Sewer, Parks, School, Fire/EMS) as they apply to a single unit, independent of how many units the project contains. Total Units only comes into play when calculating Total Impact Fees, which multiplies that fixed per-unit total by the number of units in the project.

Often, but not universally -- it depends heavily on the jurisdiction and which categories it charges for at all. Some jurisdictions charge no school impact fee, others weight water or sewer capacity heavily due to local infrastructure constraints, and Largest Percent will reflect whichever category you've entered the highest per-unit figure for, based on your own local schedule rather than a fixed rule.

Typically at building permit issuance, which is later than land acquisition or entitlement approval -- meaning the fee amount and even the fee schedule itself can change between when a project is underwritten and when the fee is actually assessed, especially on a multi-year project. Include a buffer for possible fee schedule updates when using these totals in a development pro forma.