Growth with Affordability

HALA Dashboard Growth with Affordability Strategies

What is MHA?

Mandatory Housing Affordability (MHA) is a new program to ensure that growth brings affordability. MHA will require new development to build affordable homes or contribute to a City fund for affordable housing. To put MHA into effect, we need to make zoning changes that add development capacity and expand housing choices.


MHA Implementation Citywide


Congrats Seattle! The City Council has passed the MHA Residential and Commercial Frameworks!


What is Mandatory Housing Affordability (MHA)?

MHA is a new program that would require developers to contribute to affordable housing. Read our summary to learn more.

Weekly Wonk Mandatory Housing Affordability

What's happening right now? (updated 11/30/16)


Draft zoning maps

In October 2016, we released draft maps for your input on the possible zoning changes needed to implement Mandatory Housing Affordability (MHA) in specific neighborhoods.

Environmental Impact Statement

As we consider zoning changes to implement MHA and increase housing choices, we will prepare an Environmental Impact Statement (EIS) to analyze three alternatives and identify their impacts. The EIS scoping period closed in September. Many community members provided scoping comments. In the Scoping Summary, comments are summarized with information on how they will be considered in the EIS analysis.

The next steps are to define the alternatives and prepare the impact analysis. We expect to release a Draft Environmental Impact Statement (DEIS) for public comment in March 2017.

DRAFT MHA Urban Design and Neighborhood Character Study

This report provides urban design analysis of the potential zoning changes to implement MHA. We review a range of representative development prototypes in various multifamily and commercial zones. The prototypes consider the design and scale of new development with the draft MHA capacity increases. We summarize and discuss draft zoning standards. To provide comments on this report, please email

MHA Economic Feasibility Analysis

We have prepared an economic feasibility analysis inform decisions about zoning changes to implement MHA. The analysis reviews a range of representative development prototypes in various multifamily and commercial zones. The prototypes consider the feasibility of new development with the proposed MHA affordable housing requirements and the proposed development capacity increases.

MHA Implementation in Downtown and South Lake Union

Proposal Transmitted to the City Council (November 2016)

SEPA Draft Proposal (May 2016)

Original Draft Proposal (November 2015)

MHA Residential and Commercial Frameworks

MHA-Residential Framework (adopted August 2016)

MHA-Commercial Framework (first adopted November 2015; amended December 2016)