The announcement was made on Thursday night's "Flood Relief with Vince Gill and Friends," a telethon held on local station WSMV.
The money will go to various flood relief organizations in the city rocked by deadly storms and flooding that killed 30 in three states, including 20 in Tennessee.
The gift was announced by the show's host after Swift finished an interview from her tour stop in Des Moines, Iowa.
Cleanup and repair is expected to cost more than $1 billion and thousands of homes were damaged. Pleas to donate to relief organizations started early and Nashville's musical talent - from local bands and clubs to the biggest stars - are giving their time and money to the effort.