The heavyweight blue chip saw shares leap 8% higher, contributing most of the 0.8% rise in the wider top tier, which closed 53 points higher at 6483.1.
Vodafone's impressive share gains added to improved sentiment on world markets after two days of losses as the threat of imminent military action against Syria subsided.
Cheer over the US economy also provided a boost after revised figures showed growth of 2.5% between April and June - much faster than the 1.7% previous estimation.
In currency markets, the pound remained higher against most major currencies except the dollar as it continued to benefit from upbeat comments from Bank of England governor Mark Carney on Wednesday.
Sterling rose to 1.17 euros, but remained at 1.55 dollars, as the greenback strengthened after yesterday's positive economic data.
Vodafone was the biggest riser in the FTSE-100 - up 15.5p to 204.8p - after it said it had resumed talks over the potential sale of a 45% stake in Verizon.
It is thought that partner Verizon Communications wants to pay around $100 billion (£64.4bn) for the stake, though reports have said Vodafone is pressing for as much as $130bn (£83.8bn).
The Newbury-based company is likely to set aside a large chunk of the US sale proceeds on debt repayments, share buy backs and for a war chest for acquisitions.
Other big risers included advertising and marketing giant WPP, up 49p to 1227p after it raised its full-year outlook on the back of improving demand in the UK and United States.
The world's biggest advertising agency, which is set to be overtaken by the recently-announced merger of rivals Publicis and Omnicom, said like-for-like revenues growth hit 5% last month, up from 2.4% over the first half of the year. Underlying pre-tax profits rose 12% to £524 million.
The fallers board was topped by outsourcing services firm Serco after it emerged on Thursday the Government had uncovered potentially fraudulent behaviour in the management of its £285m prison escorting contract.
The group said that revenues would be hit and new deals delayed following the latest controversy.
Investors took fright despite seeing adjusted pre-tax interim profits rise 11% to £127.1m on revenues that were up 12% to £2.55bn, with shares tumbling 11% or 68p to 538.5p.
Other big FTSE-100 risers were Melrose Industries up 17.4p to 301.8p and easyJet, which soared 47p, to 1259p.
Other big FTSE-100 fallers were Serco Antofagasta off 25.5p to 849p, Pearson 36p lower at 1280p and Vedanta Resources down 22p at 1187p.