The federal Historic Tax Credit (HTC) was eliminated in the tax reform bill passed by the House of Representatives on November 16. The current Senate version of the tax bill keeps the HTC at the current 20% level, but make changes that reduce the value of this important (and successful) historic preservation incentive. The National Park Service website explains how the tax credit works.
The legislative process is not over.   A House-Senate conference committee will reconcile the differences between the tax bills passed by each chamber. Our colleagues at the National Trust for Historic Preservation have provided a link to their online advocacy site to enable our members to send messages to Members of Congress in support of the Historic Tax Credit.