v3.26.1
Segment reporting (Details)
₨ in Millions, $ in Millions
 12 Months Ended
Mar. 31, 2026
INR (₨)
Mar. 31, 2026
USD ($)
Mar. 31, 2025
INR (₨)
Mar. 31, 2024
INR (₨)
Disclosure of operating segments [line items]        
External customers ₨ 44,877 $ 474 ₨ 39,886 ₨ 35,634
Unallocated expenses:        
Depreciation and amortization (7,274) (77) (5,633) (4,773)
Other income / (expense), net 376 4 363 379
Finance income 1 0 13 0
Finance expenses (3,963)   (2,744) (2,204)
Profit / (loss) before tax (941) (11) (286) 352
Tax (expense) / benefit (425) (4) (499) (183)
Profit/(Loss) for the year (1,366) $ (15) (785) 169
Network Connectivity Services        
Disclosure of operating segments [line items]        
External customers 17,634   15,781 14,661
Intersegment revenues 0   0 0
Operating expenses (14,309)   (13,920) (12,319)
Intersegment expenses (252)   (252) (252)
Segment operating income / (loss) 3,073   1,609 2,090
Unallocated expenses:        
Depreciation and amortization (2,452)   (2,176) (1,980)
Data center services        
Disclosure of operating segments [line items]        
External customers 17,519   14,196 11,054
Intersegment revenues 88   88 88
Operating expenses (9,544)   (7,768) (6,425)
Intersegment expenses 0   0 0
Segment operating income / (loss) 8,063   6,516 4,717
Unallocated expenses:        
Depreciation and amortization (4,474)   (3,145) (2,541)
Digital services        
Disclosure of operating segments [line items]        
External customers 9,724   9,909 9,919
Intersegment revenues 222   221 221
Operating expenses (10,790)   (10,612) (10,105)
Intersegment expenses (58)   (57) (57)
Segment operating income / (loss) (902)   (539) (22)
Unallocated expenses:        
Depreciation and amortization (348)   (312) (252)
Total Segments [Member]        
Disclosure of operating segments [line items]        
External customers 44,877   39,886 35,634
Intersegment revenues 310   309 309
Operating expenses (34,643)   (32,300) (28,849)
Intersegment expenses (310)   (309) (309)
Segment operating income / (loss) 10,234   7,586 6,785
Unallocated expenses:        
Support service unit costs (349)   (59) 9
Depreciation and amortization (7,274)   (5,633) (4,773)
Other income / (expense), net 410   551 535
Finance income 1   13 0
Finance expenses (3,963)   (2,744) (2,204)
Profit / (loss) before tax (941)   (286) 352
Tax (expense) / benefit (425)   (499) (183)
Profit/(Loss) for the year ₨ (1,366)   ₨ (785) ₨ 169