Section 18 Abuse of dominant position.C1

C2(1)

Subject to section 19, any conduct on the part of one or more undertakings which amounts to the abuse of a dominant position in a market is prohibited if it may affect trade within the United Kingdom.

(2)

Conduct may, in particular, constitute such an abuse if it consists in—

(a)

directly or indirectly imposing unfair purchase or selling prices or other unfair trading conditions;

(b)

limiting production, markets or technical development to the prejudice of consumers;

(c)

applying dissimilar conditions to equivalent transactions with other trading parties, thereby placing them at a competitive disadvantage;

(d)

making the conclusion of contracts subject to acceptance by the other parties of supplementary obligations which, by their nature or according to commercial usage, have no connection with the subject of the contracts.

(3)

In this section—

“dominant position” means a dominant position within the United Kingdom; and
“the United Kingdom” means the United Kingdom or any part of it.

(4)

The prohibition imposed by subsection (1) is referred to in this Act as “the Chapter II prohibition”.

Annotations

Modifications

C1

S. 18 restricted (31.12.2020) by S.I. 2019/93, Sch. 4 para. 17A(2) (as inserted by The Competition (Amendment etc.) (EU Exit) Regulations 2020 (S.I. 2020/1343), regs. 1(1), 40(2))

C2

S. 18(1) excluded (18.6.2001) by 2000 c. 8, s. 164(3)(5); S.I. 2001/1820, art. 2, Sch.

s. 18(1) excluded (3.9.2001) by 2000 c. 8, s. 312(2); S.I. 2001/2632, art. 2(2), Sch. Pt. 2

Notes on the whole Act

Textual amendments

F1: Words in long title substituted (1.5.2004) by The Competition Act 1998 and Other Enactments (Amendment) Regulations 2004 (S.I. 2004/1261), Sch. 1 para. 1

Notes on Part I

Modifications

C1

Pt. 1: certain functions made exercisable concurrently (26.11.1998 for certain purposes and prosp. otherwise) by 1984 c. 12, s. 50(3) (as substituted by 1998 c. 41, s. 66(5), Sch. 10 Pt. II para. 2(6) (with s. 73); S.I. 1998/2750, art. 2)

C2

Pt. 1 (except ss. 38(1)-(6), 51) amended (1.2.2001) by 2000 c. 38, ss. 86(1)(3), 89 (with ss. 105(2)(d)(5), 106); S.I. 2001/57, art. 3(1), Sch. 2 Pt. 1

C3

Pt. 1 (except ss. 38(1)-(6), 51, 52(6) and (8) and 54) amended (1.2.2001) by 2000 c. 38, s. 86(4)(b)(5) (with ss. 105(2)(d)(5), 106); S.I. 2001/57, art. 3(1), Sch. 2 Pt. 1

Pt. 1 (except ss. 38(1)-(6), 51) amended (1.2.2001) by 2000 c. 38, s. 86(7)(b) (with ss. 105(2)(d)(5), 106); S.I. 2001/57, art. 3(1), Sch. 2 Pt. 1

C4

Pt. 1 modified (25.7.2003 for specified purposes, 29.12.2003 in so far as not already in force) by Communications Act 2003 (c. 21), ss. 371(3), 411(2) (with Sch. 18); S.I. 2003/1900, arts. 1(2), 2(1), Sch. 1 (with art. 3) (as amended by S.I. 2003/3142, art. 1(3)); S.I. 2003/3142, art. 3(2) (with art. 11)

C5

Pt. 1 certain functions made exercisable concurrently by 1998 c. 41, s. 67(3) (as substituted (1.5.2004) by The Competition Act 1998 and Other Enactments (Amendment) Regulations 2004 (S.I. 2004/1261), reg. 1(a), Sch. 2 para. 6(2)(a))

C6

Pt. 1 certain functions made exercisable concurrently by 1991 c. 56, s. 31(3) (as substituted (1.5.2004) by The Competition Act 1998 and Other Enactments (Amendment) Regulations 2004 (S.I. 2004/1261), reg. 1(a), Sch. 2 para. 4(2)(a))

C7

Pt. 1 certain functions made exercisable concurrently by S.I. 1992/231 (N.I. 1) art. 46(3) (as substituted (1.5.2004) by The Competition Act 1998 and Other Enactments (Amendment) Regulations 2004 (S.I. 2004/1261), reg. 1(a), Sch. 2 para. 5(2)(a))

C8

Pt. 1 certain functions made exercisable concurrently by 1986 c. 44, s. 36A(3) (as substituted (1.5.2004) by The Competition Act 1998 and Other Enactments (Amendment) Regulations 2004 (S.I. 2004/1261), reg. 1(a), Sch. 2 para. 1(2)(a))

C9

Pt. 1 restricted (1.5.2004) by The Competition Act 1998 and Other Enactments (Amendment) Regulations 2004 (S.I. 2004/1261), regs. 1(a), 9(2)

C10

Pt. 1 certain functions made exercisable concurrently by 1989 c. 29, s. 43(3) (as substituted (1.5.2004) by The Competition Act 1998 and Other Enactments (Amendment) Regulations 2004 (S.I. 2004/1261), reg. 1(a), Sch. 2 para. 3(2)(a))

C11

Pt. 1 certain functions made exercisable concurrently by S.I. 1996/275 (N.I. 2), art. 23(3) (as substituted (1.5.2004) by The Competition Act 1998 and Other Enactments (Amendment) Regulations 2004 (S.I. 2004/1261), reg. 1(a), Sch. 2 para. 9(2)(a))

C12

Pt. 1 certain functions made exercisable concurrently (1.4.2007) by The Water and Sewerage Services (Northern Ireland) Order 2006 (S.I. 2006/3336), arts. 1(2), 29(3) (with arts. 8(8), 121(3), 307); S.R. 2007/194, art. 2(2), Sch. Pt. 2 (with Sch. 2)

C13

Pt. 1 modified (1.4.2007) by The Water and Sewerage Services (Northern Ireland) Order 2006 (S.I. 2006/3336), arts. 1(2), 29(5) (with arts. 8(8), 121(3), 307); S.R. 2007/194, art. 2(2), Sch. Pt. 2 (with Sch. 2)

C14

Pt. 1 modified (1.4.2013) by Health and Social Care Act 2012 (c. 7), ss. 72(3), 306(4); S.I. 2013/160, art. 2(2) (with arts. 7-9)

C15

Pt. 1 functions made exercisable concurrently (6.4.2013) by Civil Aviation Act 2012 (c. 19), ss. 62(1)-(3), 110(1) (with s. 77(1)-(3), Sch. 10 paras. 12, 17); S.I. 2013/589, art. 2(1)-(3)

C16

Pt. 1 modified in part (6.4.2013) by Civil Aviation Act 2012 (c. 19), ss. 62(4), 110(1) (with ss. 62(5), 77(1)-(3), Sch. 10 paras. 12, 17); S.I. 2013/589, art. 2(1)-(3)

C17

Pt. 1 certain functions made exercisable concurrently by 2000 c. 8, s. 234J (as inserted (1.11.2014 for specified purposes, 1.4.2015 so far as not already in force) by Financial Services (Banking Reform) Act 2013 (c. 33), s. 148(5), Sch. 8 para. 3; S.I. 2014/2458, arts. 2(b)(aa)(i), 3(b)(v))

C18

Pt. 1 certain functions made exercisable concurrently (1.11.2014 for specified purposes, 1.4.2015 so far as not already in force) by Financial Services (Banking Reform) Act 2013 (c. 33), ss. 61(2), 148(5); S.I. 2014/2458, arts. 2(a)(i), 3(b)(ii)

C19

Pt. 1: certain functions made exercisable concurrently (26.12.2023) by Energy Act 2023 (c. 52), ss. 37, 334(3)(a) (with s. 38)

C20

Pt. 1: certain functions made exercisable concurrently (E.W.S.) (27.1.2026 for specified purposes) by The Heat Networks (Market Framework) (Great Britain) Regulations 2025 (S.I. 2025/269), regs. 1(4)(5), 46(2)(a)

C21

Pt. 1 modified (27.1.2026 for specified purposes) (E.W.S.) by The Heat Networks (Market Framework) (Great Britain) Regulations 2025 (S.I. 2025/269), regs. 1(4)(5), 46(3)(a)