Tory shadow housing secretary Sir James Cleverly said it was “outrageous” that she had been “rewarded for dodging tax”.
He added: “Ordinary people’s tax money has been funnelled straight into her pocket.
“We asked the Government about this in Parliament and they refused to answer the question. And now we know why: she’s getting a windfall that covers nearly half the tax bill she tried to avoid.
“Rayner has long campaigned for transparency on tax affairs. Clearly, that doesn’t apply to her own cash.
“As always with Labour, it’s one rule for them, and another for everyone else. The Prime Minister should find a backbone and ensure wrongdoing is not rewarded.”
The Ashton-under-Lyne MP pushed for a ban on departing ministers who break the code collecting a payout when in opposition.
New rules came into force on Monday which mean ministers forced to quit following a “serious breach” of the code will no longer receive the payout.
Ministerial standards adviser Sir Laurie Magnus probed widely reported allegations about Ms Rayner’s property ownership at the start of September.
He said he believed she had acted in “good faith” but that “the responsibility of any taxpayer for reporting their tax returns and settling their liabilities rests ultimately with themselves”.
The ethics watchdog found Ms Rayner’s failure to settle her full stamp duty liability, along with the fact that this was only established following media scrutiny of her tax affairs, led him to consider the ministerial code had been breached.
A spokesman for Ms Rayner said: “There is a world of difference between making an honest mistake and a severe breach of the ministerial code. As the independent ethics adviser’s investigation concluded, Angela acted with integrity and an exemplary commitment to public service.”