William Cash, of Upton Cressett, near Bridgnorth, also hinted that he would like to stand as a Conservative MP.
Mr Cash, the son of Staffordshire Conservative MP Sir Bill Cash, joined Ukip in 2014 and was appointed the party's heritage and tourism spokesman.
He contested the ultra-marginal North Warwickshire seat for Ukip at the last General Election, where the Conservatives were defending a majority of just 50. The Conservatives actually increase their majority to nearly 3,000, with Mr Cash coming third.
He said the decision to stand against the Conservatives in such a closely fought seat led to him falling out with his father.
Mr Cash quit Ukip in August, saying he feared the party would lurch to the right.
He said the Conservative Party had been transformed since David Cameron and George Osborne left the government, and had been impressed by Theresa May's leadership.
Ukip deputy chairman Suzanne Evans, from Shrewsbury, said Mr Cash's contribution to the party would be missed.
She said today: "William was a fabulous heritage and tourism spokesman and I for one will very much miss his input. I've been extremely grateful for all the support he has given to me personally over the past couple of years and I wish him all the very best."
Open letter Why I have left UKIP for the Conservatives
Long-time Ukip supporter and candidate William Cash has decided to join the Tories. Here he explains his decision.
"For the first time in my life, I have joined up as a member of the Conservative Party.
It cost £25 and took less than a minute online. But it has been a long personal political odyssey; a journey that included being so disaffected with the Tory 'lite' liberal brand of so-called Conservatism espoused by Cameron/Osborne that threatened to fasten us with iron cuffs to the EU in perpetuity, that I voted Ukip in 2015.
I always supported Ukip more for reasons of saving our parliamentary sovereignty rather than concerns over 'immigration' that Nigel Farage thinks should become the party's defining issue. But that was not why I joined Ukip. For me it was more about saving the aesthetic soul of Britain rather than controlling borders, not that this wasn't an issue.
Indeed so deeply did I feel about standing up for the Great British Countryside (I am lucky enough to live in magical hamlet of Upton Cressett in the Shropshire Hills near Bridgnorth) I stood for Ukip in the Midlands seat of North Warwickshire on a pro-countryside ticket campaigning to fight to save the very 'aesthetic soul' of England from George Osborne's bulldozers parked on every village green.
I can recall exactly the day I decided to join Ukip . It was the day that Nigel Farage won the European elections in May 2014 after I entered the 22 mile Bridgnorth Charity Walk – sponsored by my wife Laura who despaired of my ever expanding girth and jowl-line.
Other than the wild beauty of the countryside (what the poet Louis Macneice called the 'idle music' of Shropshire) what struck me most about the Shropshire scenery as I trudged along was the number of Vote Ukip signs on wooden stakes displayed proudly in the houses and cottage gardens of the quintessentially English rural villages I passed through on my Shropshire walk.
Villages and places such as Neenton, Cleobury North and Ditton Priors. The sort of sleepy hamlets that never feature in Mori polls but whose rural communities were sick of planning battles. The result was a shire revolt against the anti-countryside policies of Osborne/Cameron as former Tory voters abandoned the Conservative party in hundreds of thousands.
Shropshire was in the front trenches of the countryside wars. After posters were pinned to village notice boards around the county declaring 'Our Shropshire countryside Under Threat!' over 500 people in tweeds and Barbours crammed into a Shrewsbury's Lord Hill hotel to hear speakers speak out against the governments' pro-build policies.
Judging by the dog-haired Land Rovers parked outside, most looked like they should have been middle-class rural Tory voters. But many most likely voted Ukip in the European elections, where Ukip won three out of seven seats in the West Midlands and polled 428, 010 votes against the Tories polling just 330,470 votes.
The Guardian may have call them Nimbys but in fact, it was a very English sort of shire revolution. Packed into the hotel were voters who felt betrayed by a Tory led Coalition that seems at best indifferent to the countryside and heritage that is so important for rural economies.
By the time it came to the 2015 election, I had decided that I could not support the Tory party's anti-countryside polices and ended up falling out with my Eurosceptic father Sir Bill Cash MP when I decided to fight the marginal seat of North Warwickshire where the Tories had a majority of just 50. My father's thinking was that votes for Ukip would rob the Conservatives of victory in critical shire seats that were needed if the Tory party was going to get the majority required to give the people a Referendum.
In fact, the very opposite happened. Ukip candidates like myself (I won over 8,000 votes in a working class seat that had been Labour throughout the Blair years) took votes way from Labour and ensured that the Tories won enough seats to give the people the Referendum that Cameron had promised; and was only forced to promise because of being squeezed by Eurosceptic MPs like my father and Shrosphire MP Owen Paterson and and the rise of Ukip.
After the historic Brexit victory I resigned from Ukip as soon as it was clear that Osborne/Cameron era was reduced to political ashes. I did not join the Tories then as I wanted to wait and see how Theresa May handled Brexit negotiations. Following the historic by-election victory in Copeland, and Ukip leader Paul Nuttall's failure to win in Stoke – Brexit capital of Britain – it is clear to me that Ukip has no future as a party of credible government.
I would certainly not rule out standing as a Tory MP for a Midlands seat in 2020 should I be selected by a local Conservative association. When I debated minister Philip Dunne MP over Brexit in St Mary's Church just before the Referendum, I was pleased to see the amount of local support I had for my pro-Shropshire countryside and pro-British sovereignty views – our right to govern ourselves free from interference from Brussels, a view alas not shared by Philip Dunne MP who argued the Remain case.
I support of the 'moral conservatism' (in action and deed) that lies at the heart of Theresa May's vision for a one nation 'Brexit Britain' that reaches out to both the hard working middle class and working class across the country, as shown by taking the former Labour stronghold of Copeland in the Lake District to very nearly beating Ukip in Stoke which is a poster city for inner city neglect.
I like to think that the moral Conservatism of Theresa May – a church going vicar's daughter with a strong sense of politics as a 'vocation', like Margaret Thatcher – is now returning the party to the days of the late 1950s when Quintin Hogg, then chairman of the party, said: 'Conservatism is not so much a philosophy as an attitude, a constant force...corresponding to a deep and permanent requirement of human nature itself'.
In other words leadership requires an act of faith, or even more a 'belief' in human nature. The Toryism of Osborne/Cameron was a divisive betrayal of this idea that politics and leadership requires even a view of human nature and a sense of what entering the calling of politics is really for. Whilst Osborne seemed consumed by the saturnine politics of Faustian strategy, self-interest, ego and legacy – standing for no real personal or religious belief other than the gospel of liberal EU free trade, freedom of movement and globalisation – Theresa May is the very opposite.
I voted Ukip in the election of 2015 because I felt the Tory party of David Cameron and George Osbrone had betrayed the Conservative party, not only in their appeasement of the EU nomenclature but in a series of policies that made betrayed the very principles of Conservatism that used to make the Tory party the natural party of the rural shires and home counties.
Osborne, especially, is not a true Tory interested in the sort of moral conservative vision that Theresa May seems to believe in. In America, Osborne would be a Democrat.
As for Ukip , Nuttall's loss in Stoke was hardly surprising. His campaign wasn't helped by his Walter Mitty performance and lack of consistency in his CV. Ukip has lost its way ideologically now that its very raison d'être, of leaving the EU, is now being so effectively and ruthlessly carried out by Theresa May.
It looks like Ukip has been 'found out' by the electorate as not really being a party at all – but rather just a cause or a movement. Albeit a hugely successful one at that under Nigel Farage which is why I resigned last year when he resigned as party leader."