New Hampshire Notary Stamps & Seals

Does New Hampshire require a notary stamp/seal?

Yes. New Hampshire requires a notary stamp/seal.

Source: N.H. Rev. Stat. Ann. § 455:3. Powers.
Every notary public, in addition to the usual powers of the office, shall have the same powers as a justice of the peace in relation to depositions and the acknowledgment of deeds and other instruments and the administering of oaths. All acknowledgments made by a notary public shall be either under an official seal or shall carry the legible imprint of an official rubber stamp stating the name of the notary, the words “notary public, New Hampshire” and the expiration date of the notary public’s commission.

See also N. H. Rev. Stat. Ann. § 456-B:7. Certificate of Notarial Acts.
I. A notarial act must be evidenced by a certificate signed and dated by a notarial officer. The certificate must include identification of the jurisdiction in which the notarial act is performed and the title of the office of the notarial officer and may include the official stamp or seal of office. If the officer is a notary public, the certificate must also indicate the date of expiration, if any, of the commission of office, but omission of that information may subsequently be corrected. If the officer is a commissioned officer on active duty in the military service of the United States, it must also include the officer’s rank.