World number two Federer had won all 13 of their previous encounters, with Ferrer only managing to take four sets off the Swiss master in that time.
And there was no change to that record as Federer broke his opponent late in the first set before taking the tie-break by defending a sole mini-break to complete victory in one hour and 48 minutes.
“David has been on a great run, winning (the Paris Masters) for him was so deserving as he’s put in so much effort,” Federer said afterwards. “It was two sets but a tough match, so it’s great to play well and qualify.
“You really want to keep a clean sheet going into the semis so as ever I'm going to try my best and try to beat Juan Martin (Del Potro on Friday).”
Federer was full of praise for world number five and fourth seed Ferrer, who has won seven tournaments this season at the age of 30.
“I think he’s so respected by fellow competitors, he puts in such a great effort day in day out with great sportsmanship.
“I enjoy to play against him not because of the 14-0 record but because he’s a great guy and a great player.”
It was far from straightforward initially for Federer, whose first serve was not at its magnificent best, and who found Ferrer’s dogged baseline retrieving hard work.
Indeed, the Swiss master had to save three break points in each of his opening two service games, although they sandwiched a break of his own as the normally efficient Spaniard switched off, following a double-fault with an unforced error to put a forehand long.
But retriever Ferrer was having a lot of joy against serve, and managed to break back to 3-2 after Federer went long via an unsuccessful challenge.
Federer still had an extra gear though and he clicked into it while the Spaniard was serving to stay in it, showing great poise to bully his opponent at the baseline before turning from a series of backhands to a spinning forehand that saw him break to love and claim the opening set.
Both men held serve throughout the second set, although again Ferrer came close as he spurned two break points in the opening Federer service game, a supreme drop shot completing the comeback.
Federer is a master of many skills, and the tie-break is one of them. He earned a mini-break as a flashing return caught Ferrer off guard and, from 4-2, the Spaniard did not have a sniff as his opponent found a pair of hitherto been rare aces to close it out 7-5.
That means Federer is guaranteed a place in the semis, with the two-times winner in London - and four-times champ of the previous Masters Cup format - seeking to defend his title once more.
Ferrer, who beat Del Potro in a three-set match, can still qualify, as can the Argentine and even Janko Tipsarevic, although the complex permutations will not take shape until Friday.
6-Juan Martin Del Potro (Argentina) beat 8-Janko Tipsarevic (Serbia) 6-0 6-4
2-Roger Federer (Switzerland) beat 4-David Ferrer (Spain) 6-4 7-6(5)