The answer is "yes". See Corollary 2 on page 119 of Thurston's article A norm for the homology of 3-manifolds.
In fact, fibered knots fibre in exactly one way. And all minimal genus Seifert surfaces (for a fixed fibered knot) are isotopic.
Since Thurston's paper is not immediately and obviously available online (?), I googled around and found A survey of the Thurston norm. See Example 2.4 therein.