| Document and Entity Information | Jan. 23, 2025 |
| Document Information [Line Items] | |
| Document Type | 8-K |
| Document Period End Date | Jan. 23, 2025 |
| Entity Registrant Name | WNS (HOLDINGS) LIMITED |
| Entity Incorporation State Country Code | Y9 |
| Entity File Number | 001-32945 |
| Entity Tax Identification Number | 00-0000000 |
| Entity Address Address Line 1 | 515 Madison Avenue, 8th Floor |
| Entity Address Address Line 2 | Pirojshanagar |
| Entity Address Address Line 3 | Vikhroli (W) |
| Entity Address City Or Town | New York |
| Entity Address State Or Province | NY |
| Entity Address Postal Zip Code | 10022 |
| Country Region | 91 |
| City Area Code | 22 |
| Local Phone Number | 6826-2100 |
| Written Communications | false |
| Soliciting Material | false |
| Pre Commencement Tender Offer | false |
| Pre Commencement Issuer Tender Offer | false |
| Security 12b Title | Ordinary share, par value 10 pence per share |
| Trading Symbol | WNS |
| Security Exchange Name | NYSE |
| Entity Emerging Growth Company | false |
| Amendment Flag | false |
| Entity Central Index Key | 0001356570 |
| Other Business [Member] | |
| Document Information [Line Items] | |
| Entity Address Address Line 1 | Gate 4, Godrej & Boyce Complex |
| Entity Address Address Line 2 | Pirojshanagar |
| Entity Address Address Line 3 | Vikhroli (W) |
| Entity Address City Or Town | Mumbai |
| Entity Address Country | IN |
| Entity Address Postal Zip Code | 400 079 |
| Other Address [Member] | |
| Document Information [Line Items] | |
| Entity Address Address Line 1 | Malta House, 36-38 Piccadilly |
| Entity Address City Or Town | London |
| Entity Address State Or Province | NY |
| Entity Address Postal Zip Code | W1J 0DP |
