v3.25.4
Property, plant and equipment (Details 3) - BRL (R$)
R$ in Thousands
12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
PROPERTY, PLANT AND EQUIPMENT      
Balance at beginning of the period R$ 46,812,381 R$ 46,318,147  
Additions [1] 10,108,587 11,075,032  
Subletting (4,873) (65,290)  
Depreciation on lease (3,723,418) (3,453,239) R$ 3,049,570
Decrease Through Cancellation Of Contracts, Property, Plant And Equipment   (74,258)  
Balance at end of the period 47,357,040 46,812,381 46,318,147
Gross carrying amount      
PROPERTY, PLANT AND EQUIPMENT      
Balance at beginning of the period 185,180,626    
Balance at end of the period 195,098,914 185,180,626  
Accumulated depreciation and amortisation      
PROPERTY, PLANT AND EQUIPMENT      
Balance at beginning of the period (138,368,245)    
Balance at end of the period (147,741,874) (138,368,245)  
Infrastructure      
PROPERTY, PLANT AND EQUIPMENT      
Balance at beginning of the period 15,990,041 14,929,179  
Additions [1] 3,636,211 4,707,950  
Subletting (4,873) (65,290)  
Balance at end of the period 17,402,210 15,990,041 14,929,179
Infrastructure | Gross carrying amount      
PROPERTY, PLANT AND EQUIPMENT      
Balance at beginning of the period 47,318,029    
Balance at end of the period 52,291,576 47,318,029  
Infrastructure | Accumulated depreciation and amortisation      
PROPERTY, PLANT AND EQUIPMENT      
Balance at beginning of the period (31,327,988)    
Balance at end of the period (34,889,366) (31,327,988)  
Switching and transmission equipment      
PROPERTY, PLANT AND EQUIPMENT      
Balance at beginning of the period 22,770,806 23,266,868  
Additions [1] 140,156 162,171  
Balance at end of the period 21,709,525 22,770,806 23,266,868
Switching and transmission equipment | Gross carrying amount      
PROPERTY, PLANT AND EQUIPMENT      
Balance at beginning of the period 91,758,158    
Balance at end of the period 94,868,938 91,758,158  
Switching and transmission equipment | Accumulated depreciation and amortisation      
PROPERTY, PLANT AND EQUIPMENT      
Balance at beginning of the period (68,987,352)    
Balance at end of the period (73,159,413) (68,987,352)  
Other property, plant and equipment      
PROPERTY, PLANT AND EQUIPMENT      
Balance at beginning of the period 453,959 512,930  
Additions [1] 171,553 117,026  
Balance at end of the period 434,919 453,959 512,930
Other property, plant and equipment | Gross carrying amount      
PROPERTY, PLANT AND EQUIPMENT      
Balance at beginning of the period 5,945,185    
Balance at end of the period 6,078,455 5,945,185  
Other property, plant and equipment | Accumulated depreciation and amortisation      
PROPERTY, PLANT AND EQUIPMENT      
Balance at beginning of the period (5,491,226)    
Balance at end of the period (5,643,536) (5,491,226)  
FiBrasil Infraestrutura e Fibra Otica S.A. ("FiBrasil")      
PROPERTY, PLANT AND EQUIPMENT      
Acquisitions through business combinations, property, plant and equipment 1,679,502    
FiBrasil Infraestrutura e Fibra Otica S.A. ("FiBrasil") | Infrastructure      
PROPERTY, PLANT AND EQUIPMENT      
Acquisitions through business combinations, property, plant and equipment 1,563,540    
FiBrasil Infraestrutura e Fibra Otica S.A. ("FiBrasil") | Other property, plant and equipment      
PROPERTY, PLANT AND EQUIPMENT      
Acquisitions through business combinations, property, plant and equipment 1,061    
Telefonica Cibersegurana e Tecnologia Do Brasil      
PROPERTY, PLANT AND EQUIPMENT      
Acquisitions through business combinations, property, plant and equipment 5,155    
Telefonica Cibersegurana e Tecnologia Do Brasil | Infrastructure      
PROPERTY, PLANT AND EQUIPMENT      
Acquisitions through business combinations, property, plant and equipment 505    
Telefonica Cibersegurana e Tecnologia Do Brasil | Switching and transmission equipment      
PROPERTY, PLANT AND EQUIPMENT      
Acquisitions through business combinations, property, plant and equipment 2,800    
Telefonica Cibersegurana e Tecnologia Do Brasil | Other property, plant and equipment      
PROPERTY, PLANT AND EQUIPMENT      
Acquisitions through business combinations, property, plant and equipment 990    
Changes in leases, after the adoption of IFRS 16      
PROPERTY, PLANT AND EQUIPMENT      
Balance at beginning of the period 13,247,618 12,080,117  
Additions 3,700,137 4,774,379  
Subletting (4,873) (65,290)  
Decrease Through Cancellation Of Contracts, Property, Plant And Equipment (214,127) (84,402)  
Other changes on leases   (3,947)  
Balance at end of the period 13,116,047 13,247,618 12,080,117
Changes in leases, after the adoption of IFRS 16 | Gross carrying amount      
PROPERTY, PLANT AND EQUIPMENT      
Balance at beginning of the period 30,069,796    
Balance at end of the period 32,845,934 30,069,796  
Changes in leases, after the adoption of IFRS 16 | Accumulated depreciation and amortisation      
PROPERTY, PLANT AND EQUIPMENT      
Balance at beginning of the period (16,822,178)    
Balance at end of the period (19,729,887) (16,822,178)  
Changes in leases, after the adoption of IFRS 16 | Infrastructure      
PROPERTY, PLANT AND EQUIPMENT      
Balance at beginning of the period 12,989,228 11,862,992  
Additions 3,508,375 4,634,552  
Subletting (4,873) (65,290)  
Depreciation And Write Offs, Net, I F R S 16, Property, Plant And Equipment (3,615,053) (3,364,821)  
Decrease Through Cancellation Of Contracts, Property, Plant And Equipment (213,077)    
Other changes on leases   (3,947)  
Balance at end of the period 12,775,310 12,989,228 11,862,992
Changes in leases, after the adoption of IFRS 16 | Infrastructure | Gross carrying amount      
PROPERTY, PLANT AND EQUIPMENT      
Balance at beginning of the period 29,418,847    
Balance at end of the period 32,014,344 29,418,847  
Changes in leases, after the adoption of IFRS 16 | Infrastructure | Accumulated depreciation and amortisation      
PROPERTY, PLANT AND EQUIPMENT      
Balance at beginning of the period (16,429,619)    
Balance at end of the period (19,239,034) (16,429,619)  
Changes in leases, after the adoption of IFRS 16 | Switching and transmission equipment      
PROPERTY, PLANT AND EQUIPMENT      
Balance at beginning of the period 253,131 203,519  
Additions 128,257 139,125  
Depreciation And Write Offs, Net, I F R S 16, Property, Plant And Equipment (89,852) (79,390)  
Decrease Through Cancellation Of Contracts, Property, Plant And Equipment (1,050) (10,123)  
Balance at end of the period 290,486 253,131 203,519
Changes in leases, after the adoption of IFRS 16 | Switching and transmission equipment | Gross carrying amount      
PROPERTY, PLANT AND EQUIPMENT      
Balance at beginning of the period 520,634    
Balance at end of the period 638,473 520,634  
Changes in leases, after the adoption of IFRS 16 | Switching and transmission equipment | Accumulated depreciation and amortisation      
PROPERTY, PLANT AND EQUIPMENT      
Balance at beginning of the period (267,503)    
Balance at end of the period (347,987) (267,503)  
Changes in leases, after the adoption of IFRS 16 | Other property, plant and equipment      
PROPERTY, PLANT AND EQUIPMENT      
Balance at beginning of the period 5,259 13,606  
Additions 63,505 702  
Depreciation And Write Offs, Net, I F R S 16, Property, Plant And Equipment (18,513) (9,028)  
Decrease Through Cancellation Of Contracts, Property, Plant And Equipment   (21)  
Balance at end of the period 50,251 5,259 R$ 13,606
Changes in leases, after the adoption of IFRS 16 | Other property, plant and equipment | Gross carrying amount      
PROPERTY, PLANT AND EQUIPMENT      
Balance at beginning of the period 130,315    
Balance at end of the period 193,117 130,315  
Changes in leases, after the adoption of IFRS 16 | Other property, plant and equipment | Accumulated depreciation and amortisation      
PROPERTY, PLANT AND EQUIPMENT      
Balance at beginning of the period (125,056)    
Balance at end of the period (142,866) R$ (125,056)  
Changes in leases, after the adoption of IFRS 16 | FiBrasil Infraestrutura e Fibra Otica S.A. ("FiBrasil")      
PROPERTY, PLANT AND EQUIPMENT      
Acquisitions through business combinations, property, plant and equipment 110,330    
Changes in leases, after the adoption of IFRS 16 | Telefonica Cibersegurana e Tecnologia Do Brasil      
PROPERTY, PLANT AND EQUIPMENT      
Acquisitions through business combinations, property, plant and equipment 380    
Changes in leases, after the adoption of IFRS 16 | Telefonica Cibersegurana e Tecnologia Do Brasil | Infrastructure      
PROPERTY, PLANT AND EQUIPMENT      
Acquisitions through business combinations, property, plant and equipment R$ 380    
[1] Additions from property and equipment mainly refers to: (i) in 2025 Investments were primarily directed towards expanding the 5G mobile network and strengthening FTTH to support the growth of connected customers. These investments demonstrate the Company's commitment to the quality of services provided, ensuring robust and consistent commercial performance throughout the year, in both B2C and B2B; .(ii) in 2024: Investments were primarily directed towards accelerating the 5G mobile network, as well as strengthening transmission backhaul, backbone and network, and FTTH customers. These were some of the initiatives that boosted our commercial growth this year, reinforcing our commitment to the quality of our services and ensuring healthy and consistent growth.