It depends on when you consider the period of “Medieval England” to have finished, but the astrologer, occult philosopher, mathematician and navigator, John Dee (1527-1608) might just make the cut. He was, among a lot of other things, astrologer and occult adviser to the court of Queen Elizabeth I. However this could be more likely counted as the start of the Renaissance.

As an early medievalist, I can't speak to the whole of medieval England, but a number of tenth and eleventh century law codes prescribe exile or execution for wizards:

"Concerning witchcrafts. And we have pronounced concerning witchcrafts and sorceries and secret attempts on life, that, if anyone is killed by such, and he [the accused] cannot deny it, he is to forfeit his life. If, however, he wish to deny it, and is convicted at the three-fold ordeal, he is to be 120 days in prison; and the kinsmen are afterwards to take him out and to pay 120 shillings to the king, and to pay the wergild to his kinsmen, and to stand surety for him that he will desist from such for ever." -II Aethelstan, 926-930

"If wizards or sorcerers, perjurers, or murderers or foul, polluted manifest whores are caught anywhere in the land, they are then to be driven from this country and the nation is to be purified, or they are to be completely destroyed in this country, unless they desist and atone very deeply." -Laws of Edward and Guthrum, a forged code that circulated as royal law, written in the first decade of the eleventh century

"It is heathen practice if one worships idols, namely if one worships heathen gods and the sun or the moon, fire or flood, wells or stones or any kind of forest trees, or if one practices witchcraft or encompasses death by any means, either by sacrifice or divination, or takes any part in such delusions." -II Cnut, early 1020s

The lines between Wizardry, natural philosophy and being a learned individual were particularly blurred up to the middle ages. I don't know of any official court mystics that went by the title 'Wizard' in the Kingdom of England, but most noble courts including England would have natural philosophers and more relevant to your question would have alchemists who sought to transmute the natural properties of the world.

Not all of these Alchemists were fakes, although certainly many misinterpreted or lied about their results. The most relevant person who I can see as close to the position of a wizard would be Roger Bacon whose Opus Majus is a well known source of mysticism/natural philosophy of the time.

If you would like a short lecture on Alchemists I recommend 'In our Time' for a detailed basis.