What is the status of a patent application after a notice of allowance is mailed?

Once a nonprovisional patent application has been examined and determined to meet all statutory requirements, a notice of allowance is sent to the applicant. The status of the application is then considered “allowed” or “in issue”. As per MPEP 203.04:

An “allowed” nonprovisional application or an application “in issue” is one which has been examined and determined to meet all statutory requirements, and in which a notice of allowance has been sent to the applicant. Its status as an “allowed” application continues from the date of the notice of allowance until it issues as a patent, unless it is withdrawn from issue (37 CFR 1.313), or becomes abandoned for failure to pay the issue fee and any required publication fee (37 CFR 1.314 and 1.316).