Despite the ability of cephalopods to move freely through the sea, their geographic distribution patterns tend to be restricted. Many genera but few species were widely distributed in the past. In fact, it is by means of distribution patterns at the generic level that most interregional correlations based on cephalopods are made.

Carboniferous ammonoids common to strata on both sides of the Atlantic Ocean in the Northern Hemisphere include: Protocanites lyoni (Meek and Worthen) in the late Kinderhookian and late Tournaisian; Goniatites crenistria Phillips in the late Meramecan and late Visean; G. granosus Portlock and Neoglyphioceras subcirculare (Miller) in the early Chesterian and late Visean; Eumorphoceras bisulcatum Girty, Anthracoceras paucilobum (Phillips), and Delepinoceras bressoni Ruzhentsev in the late Chesterian and early Namurian; Branneroceras branneri (Smith) in the Morrowan, middle Namurian, and Bashkirian; and Politoceras politum (Shumard) in the Desmoinesian and Westphalian C. These few species constitute the principal "pegs" on which the correlation framework is hung. Apparent lack of species common to both sides of the Atlantic in Late Pennsylvanian and Permian deposits may result from more complicated sutures, which make differentiation in these ammonoids easier to establish.

Nautiloids generally tend to have greater stratigraphic ranges than ammonoids, but some were just as restricted stratigraphically and equally distributed geographically as some ammonoids. A few coleoids also had moderately extensive geographic ranges.

Factors that probably influenced cephalopod distribution include swimming and feeding habits, reproduction, buoyancy, sea-water properties (pH, salinity, other chemical features of the sea water, and prevailing currents), physical barriers, and type of bottom.

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