As verbs the difference between stipulate and formulate
is that
stipulate is to require (something) as a condition of a contract or agreement while
formulate is to reduce to, or express in, a formula; to put in a clear and definite form of statement or expression.
As an adjective stipulate
is (botany) having stipules; that is, having outgrowths borne on either side of the base of the leafstalk.