An outer column for a telescopic steering apparatus, comprising: a slit formed in one end section in an axial direction of the outer column; a pair of held-plate sections (32a, 32b) provided in positions on both sides of the slit in a width direction of the outer column and having long holes that are formed in portions of the held-plate sections (32a, 32b) that are aligned with each other to extend in the axial direction; and a lock through hole formed in a portion that is separated in the axial direction from the held-plate sections (32a, 32b), with a phase of the lock through hole in a circumferential direction of the outer column being separated from a center axis of the slit; the slit having an H shape as seen in a radial direction of the outer column, and comprising: a main-slit section formed in the axial direction, and a pair of sub-slit sections (40a, 40b) formed in the circumferential direction at both end sections in the axial direction of the main-slit section, with end sections in the axial direction of the main-slit section being continuous with middle sections in the circumferential direction of the sub-slit sections (40a, 40b); characterised in that the pair of the sub-slit sections (40a, 40b) have four end sections, the four end sections each having a length in the circumferential direction from the main-slit sections, and at least the length in the circumferential direction from the main-slit section of a closest-end section of one sub-slit section of the pair of the sub-slit sections (40a, 40b) which is located on a side close to the lock through hole in the axial direction, that is located in a portion close to the lock through hole in the circumferential direction is shorter than the lengths in the circumferential direction from the main-slit section of the other end sections of the pair of sub-slit sections (40a, 40b), and in that, in another sub-slit section of the pair of the sub-slit sections (40a, 40b) which is located on a far side from the lock through hole in the axial direction, the length in the circumferential direction from the main-slit section of one end section of the other sub-slit section that is a farthest end section from the lock through hole located at a position diagonal to the closest end section is shorter than the length in the circumferential direction from the main-slit section of other end section of the other sub-slit section. a slit formed in one end section in an axial direction of the outer column; a pair of held-plate sections (32a, 32b) provided in positions on both sides of the slit in a width direction of the outer column and having long holes that are formed in portions of the held-plate sections (32a, 32b) that are aligned with each other to extend in the axial direction; and a lock through hole formed in a portion that is separated in the axial direction from the held-plate sections (32a, 32b), with a phase of the lock through hole in a circumferential direction of the outer column being separated from a center axis of the slit; the slit having an H shape as seen in a radial direction of the outer column, and comprising: a main-slit section formed in the axial direction, and a pair of sub-slit sections (40a, 40b) formed in the circumferential direction at both end sections in the axial direction of the main-slit section, with end sections in the axial direction of the main-slit section being continuous with middle sections in the circumferential direction of the sub-slit sections (40a, 40b); characterised in that the pair of the sub-slit sections (40a, 40b) have four end sections, the four end sections each having a length in the circumferential direction from the main-slit sections, and at least the length in the circumferential direction from the main-slit section of a closest-end section of one sub-slit section of the pair of the sub-slit sections (40a, 40b) which is located on a side close to the lock through hole in the axial direction, that is located in a portion close to the lock through hole in the circumferential direction is shorter than the lengths in the circumferential direction from the main-slit section of the other end sections of the pair of sub-slit sections (40a, 40b), and in that, in another sub-slit section of the pair of the sub-slit sections (40a, 40b) which is located on a far side from the lock through hole in the axial direction, the length in the circumferential direction from the main-slit section of one end section of the other sub-slit section that is a farthest end section from the lock through hole located at a position diagonal to the closest end section is shorter than the length in the circumferential direction from the main-slit section of other end section of the other sub-slit section.