I just efiled but I forgot to list a rental income from a different state

[DavidD66]

If your return is accepted, you will need to file an amended return.  You should to see if your return is accepted, if not then you can correct the e-file error and add the rental income before resubmitting.  It is accepted, be sure to wait until you have received your refund if you are expecting one, or your payment has been processed if you owed and paid.