Using neutron powder diffraction on W-type hexaferrites, planar magnetic ordering described inCm′cm′ was found for SrCo2Fe16O27and SrCoZnFe16O27, while SrZn2Fe16O27had uniaxial ordering described inP63/mm′c′. Thermomagnetic measurements above room temperature also indicated magnetic transitions for SrCo2Fe16O27and SrCoZnFe16O27.