The Leeds based specialist has been trading for 33 years and worked on high profile jobs across the UK.
But a series of unpaid and disputed bills and the legal cost of chasing bad debts has forced the firm under.
The final blow to Wetheralds was £150,000 outstanding for work for Simons Group which went into administration last month.
That came on top of £911,000 worth of unpaid work for Shaylor which went into administration this summer and other disputed bills still owed by main contractors and clients.
Wetheralds director Mark Murphy told the Enquirer: “We’ve never seen anything like this in all our years in business.
“In all that time we’ve never not paid a supplier but bigger firms are a law unto themselves now.
“Just this morning I’ve had a pay less notice from a main contractor looking to knock thousands of our bill.
“The evidence for that is a few spurious photos of damage to our work which was done by someone else.
“Pay less notices and major firms not paying are driving good firms out of business.”
A letter sent to suppliers by Wetheralds said: “On the strength of advice from different specialist lawyers as to the recoverability of monies contractually due, we have soldiered on.
“But months down the line, little if any progress has been made, apart from some eye watering legal bills none of the debts were secured or cleared.
“The amounts involved for a company of our size are unsustainable.
“I am very sorry for the impact this will have on you as a longstanding supplier, but trust that in the circumstances you will understand the reasoning behind the decisions.”