You generally do not need to amend for Federal.
However, taxpayers would have to file an amended return if they did not originally claim the EITC or other credits, but now are eligible because the [unemployment comp] exclusion changed their income. These taxpayers may want to review their state tax returns as well.
IRS to recalculate taxes on unemployment benefits; refunds to start in May | Internal Revenue Servic...
See these re State:
How is my state taxing unemployment income? (intuit.com)
