Flintoff, 32, popularly known as Fred, retired from Test cricket last year after helping England regain the Ashes from Australia.
He has been recuperating since undergoing reconstructive knee surgery after the final Test at the Oval and is still ambitious to represent England in One-day cricket.
Flintoff had initially targeted England's One-day series in Bangladesh in February for his comeback but had to abandon that plan while conducting his rehabilitation in Dubai.
"Fred was with us last week and he had a long interview with Mike Watkinson (the cricket manager at Lancashire) and he said he is on course," Lancashire chief executive Jim Cumbes told reporters.
"He is full of enthusiasm. It's amazing that with the time he has been out he is still able to plough on. We are hoping to have him back by the end of July or start of August," he added.
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