Except when a guaranty is deemed an original obligation as provided in section 22-01-05, a guaranty must be in writing and signed by the guarantor, but the writing need not express a consideration.
N.D. Cent. Code § 22-01-04
Guaranty to be in writing - Exception - Consideration need not be expressed
Official source: North Dakota Legislative Branch. Reproduced from public-domain North Dakota statutes; confirm against the official source for the current text. Not legal advice.