Do I need to register with SAM.gov to be able to do my ARPA reporting due by April 30th?

Registering with SAM.gov is a requirement of your ARPA award (see Terms and Conditions, page 3, item 9.b.ii.), however you do not need to already be registered to access Treasury's portal.  

More resources on registering with SAM.gov will be provided on the Treasury website.