Affordable Unit & Cash-in-lieu Calculator

The City of Boulder Inclusionary Housing Program (IH) requires that developments of 5 or more dwelling units provide 25% and 4 or fewer dwelling units provide 20% of all new residential development as permanently affordable housing. For-sale developments are expected to provide at least half of the required affordable units on-site, the other half may be satisfied through the following options:

  1. providing affordable units off-site;
  2. making a cash-in-lieu (CIL) contribution; or
  3. donating land.

Rental developments may satisfy IH with any of the above options.

The program includes incentives when more than half of any required FOR-SALE affordable units are provided on-site.

Housing staff are available to walk you through the calculator. Note that the estimates generated by the calculator must be verified by the city. The calculations generated by this calculator are not transmitted to city staff. In order to satisfy the IH requirement, you will need to include additional steps and details NOT included in the calculator.

When your development is ready for a city review or two weeks prior to a residential building permit submittal, contact a housing planner at

How To Use the Calculator

  • To scroll in the spread sheet use the PAGE scroll bar NOT the scroll bar with-in the spread sheet.
  • Input data in the “project input” tab in the YELLOW fields
  • Developments with greater than 4 units but having fewer than 4 units in of any ONE TYPE should STOP and contact a housing planner. For example, a 50-unit development that has 4 townhome units (Townhome & Small Attached) and a multi-family building with 23 units (Attached) cannot use the calculator accurately.
  • Click on the “Options Summary” tab to see estimates for required affordable units and/or cash-in-lieu.

IMPORTANT NOTE: The Inclusionary Housing Unit & Cash-in-Lieu Calculator may not be compatible with Safari Browser. Please use an alternate browser for this tool.