CityFibre delivered a record performance in 2016, with its pure fibre networks now deployed in 42 cities across the UK.
According to the fibre broadband provider, 5,063 new connections worth £75.5 million were added last year. This compares with 1,100 connections worth £23 million in 2015.
The number of connected premises also rose significantly in 2016, going up from 1,200 to 3,962.
As a result, CityFibre is confident its revenues for the year will pass the £15 million mark.
Commenting on the figures, Chief Executive Greg Mesch said 2016 had been "a transformational year for CityFibre".
"Having started the year with a step change acquisition which significantly scaled our operational footprint across the UK, we followed up by rolling out a commercialisation campaign which delivered over 1,700 connections on the acquired assets," he said.
"The acquisition of the Redcentric network assets in September and further organic development takes our UK city footprint to 42 as we begin 2017."
Mr Mesch therefore believes CityFibre is now the largest wholesale infrastructure provider next to Openreach.
This, he said, gives the company "a great platform for future growth, including significant upsides in fibre-to-the-tower and fibre-to-the-home".
The release of the figures comes shortly after CityFibre announced that it is to expand its next-generation pure fibre broadband network in Stirling.
Construction will begin in June 2017 and see Stirling become Scotland's fourth so-called Gigabit City.