The midfielder is undergoing a medical now and if all goes well he will sign a four-year-deal.
He failed to make an impact at Stamford Bridge after signing from Reading on a free transfer last summer.
Villa are expected to shell out £5m.
For once Chelsea seem to have made some money on a transfer.
Chelsea could use the cash as a deal-breaker to keep Frank Lampard at the Bridge.
The England midfielder says he wants to stay, Chelsea have rebuffed Inter Milan's initial offer, so the signs are that Lampard could stay.
The £5m from Villa might be used to cover some of Lampard's apparent demands for a £140k per week five-year-deal.
Chelsea will probably offer the cash but will baulk at going for such a long deal for the 30-year-old.
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