Can a notary sign on a different day? 

This is a tricky question and a bit vague if you ask me.  The date of a notarization corresponds to the date that the signer signs the notary journal (according to me).  Some signers will sign for an acknowledged signature a minute, day, week, month, year, or decade before the notarization, and that is legal according to California notary law, and probably in most if not all other states.  For Jurats, the signature must be made while personally appearing before a notary public.  Oaths should ideally have an accompanying journal entry, however, there is no signature on a purely oral Oath (BTW… jurats are used with written statements that have an accompanying oath).
 
So, in all types of notary acts, the signer should ideally sign the notary journal, and the date and time when they sign the journal establishes the notarization date.  Please keep in mind that a signing where the signer signs the document at 11:59pm and signs the notary journal at 12:01am the following day could be dated either day, but I prefer my golden rule of dating the notarization when the journal is signed.
 
The document date can be the date of the notarization or before, but is generally not after.
The signing date for an acknowledged signature can be the date of the acknowledgment or before, but never after
 
So, there are three dates that might concern the notary.  It is a crime to backdate a notary certificate, but putting a previous date in the certificate wording. It is also a crime to post date the date in the certificate wording.
 
So, what does it really mean to ask, “Can a notary sign on a different day?”
 
If the notarization takes place on Monday, where the signer signs the document by Monday, and signs the journal on Monday, can the notary seal and stamp the certificate wording on Tuesday if the notary has possession of the document?  This is not recommended, and is neglegence. However, if the signing was a late night signing on Monday, and you sign and affix your stamp to the document in your possession early Tuesday morning, that is still unacceptable, but sounds less unreasonable than letting it slide 24 or 48 hours!
 
So, the official answer to the above question is — NO!  Sign the certificate within a minute or two of when the journal is signed if humanly possible.

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