These are the Official Charts Company's UK Indie Chart number-one singles of 2015.
| † | Best-selling indie single of the year |
| Issue date | Single | Artist(s) | Record label | Ref. |
|---|---|---|---|---|
| 3 January | "Got No Fans" | Wealdstone Raider | Wealdstone Records | [1] |
| 10 January | "6 Words" | Wretch 32 | Ministry of Sound | [2] |
| 17 January | "Promesses" | Tchami featuring Kaleem Taylor | [3] | |
| 24 January | [4] | |||
| 31 January | [5] | |||
| 7 February | [6] | |||
| 14 February | "Outlines" | Mike Mago featuring Dragonette | [7] | |
| 21 February | "Gravity" | DJ Fresh featuring Ella Eyre | [8] | |
| 28 February | [9] | |||
| 7 March | [10] | |||
| 14 March | [11] | |||
| 21 March | [12] | |||
| 28 March | [13] | |||
| 4 April | [14] | |||
| 11 April | [15] | |||
| 18 April | "Lean On" | Major Lazer and DJ Snake featuring MØ | Because Music | [16] |
| 25 April | "Can't Stop Playing (Makes Me High)" | Dr. Kucho! and Gregor Salto featuring Ane Brun | Ministry Of Sound | [17] |
| 2 May | "Lean On" | Major Lazer and DJ Snake featuring MØ | Because Music | [18] |
| 9 May | [19] | |||
| 16 May | [20] | |||
| 23 May | [21] | |||
| 30 May | [22] | |||
| 6 June | [23] | |||
| 13 June | [24] | |||
| 20 June | [25] | |||
| 27 June | [26] | |||
| 4 July | [27] | |||
| 11 July | [28] | |||
| 16 July | [29] | |||
| 23 July | [30] | |||
| 30 July | [31] | |||
| 6 August | [32] | |||
| 13 August | [33] | |||
| 20 August | [34] | |||
| 27 August | [35] | |||
| 3 September | [36] | |||
| 10 September | [37] | |||
| 17 September [a] | "Easy Love" | Sigala | Ministry Of Sound | [38] |
| 24 September | [39] | |||
| 1 October | [40] | |||
| 8 October | [41] | |||
| 15 October | [42] | |||
| 22 October | [43] | |||
| 29 October [a] | "Turn the Music Louder (Rumble)" | KDA featuring Tinie Tempah and Katy B | [44] | |
| 5 November [a] | "Hello" † | Adele | XL | [45] |
| 12 November [a] | [46] | |||
| 19 November [a] | [47] | |||
| 26 November | [48] | |||
| 3 December | [49] | |||
| 10 December | "Sweet Lovin'" | Sigala featuring Bryn Christopher | Ministry Of Sound | [50] |
| 17 December | "Hello" † | Adele | XL | [51] |
| 24 December [a] | "A Bridge over You" | Lewisham and Greenwich NHS Choir | EmuBands | [52] |
| Position | Artist | Weeks at number one |
|---|---|---|
| 1 | Major Lazer | 21 |
| 2 | DJ Fresh | 8 |
| 3 | Adele | 7 |
| 3 | Sigala | 7 |
| 4 | Tchami | 4 |
| 5 | Ane Brun | 1 |
| 5 | Dr. Kucho! | 1 |
| 5 | Gregor Salto | 1 |
| 5 | KDA | 1 |
| 5 | Lewisham and Greenwich NHS Choir | 1 |
| 5 | Mike Mago | 1 |
| 5 | Wealdstone Raider | 1 |
| 5 | Wretch 32 | 1 |