The invention relates to a read only magnetic information carrier (1b, 1c, 1d) comprising a substrate (2), an information layer (3) and a stabilizing layer (15a, 15b). The information layer (3) comprises a pattern of magnetic bits (4) of magnetic material wherein the pattern of magnetic bits (4) constitutes an array of bit locations. The presence or absence of the magnetic material at a bit location represents a value of the bit location by a magnetic field (5) having a predetermined magnetization direction (6). The stabilizing layer (15a, 15b) is arranged between the substrate (2) and the information layer (3) and comprises hard magnetic material (8, 9) which is magnetically coupled to the magnetic material of the magnetic bit (4). The magnetically coupled hard magnetic material (8, 9) provides the predetermined magnetization direction (6) of the magnetic field (5). The magnetic coupling between the hard magnetic material (8, 9) and the magnetic bits (4) prevents the predetermined magnetization direction (6) of the magnetized material of the magnetic bits (4) to change, which improves the thermal stability of the magnetic bits (4).