Pavitt has been leading IT at NTL for about two and a half years and won't immediately be moving to another company, though he said he will ultimately be looking for another CIO position, probably within a telecoms, media or utilities company.
In a market squeezed on one side by BT and on another by BSkyB, as well as the Freeview digital TV platform, NTL has been criticised for poor customer service at times. This was one effect of cable industry consolidation in the 1990s that saw NTL acquire a number of other providers and try to marry various systems and call centres.
However, Pavitt has led projects to put right some of the problems, most notably a single-view back-end and front-end customer service IT setup called Harmony, mainly based on .Net and SQL Server technology from Microsoft.
Pavitt told ZDNet UK sister site silicon.com today: "We have taken IT in NTL from something that was very unconsolidated, inefficient and expensive to something that is above average in all those areas. Our trajectory now is for the best IT in terms of total cost of ownership and what we will physically deliver."
He added that he will leave "good legacies" and that his decision to leave is based on his "own personal values" -- and feeling rather burnt out after lots of hard work.
NTL will now appoint an interim CIO and while Pavitt says there is a list of candidates internally for the CIO post, no decision has been made.
Speculation will now turn to the CIO at Telewest, the other main UK cable company whose business complements NTL's, who could head up a combined IT function.