E.ON and Age UK are to temporarily stop offering a branded energy tariff following criticism of the deal, citing "continued speculation regarding the partnership".
Age UK was criticised for exploiting its position as a trusted charity after it was claimed E.ON paid it £6 million a year in return for the charity pushing expensive tariffs to the elderly.
An E.ON spokesman said: "This decision has been reached on a mutual basis and both organisations retain confidence in the tariff offered to customers.
"However, due to continued speculation regarding the partnership, both organisations feel it is right to pause and reflect on the best way for both parties to achieve their shared goal of helping customers."
The change will come into effect on Wednesday February 10.
The move comes after The Sun newspaper revealed it found details of E.ON payments to the charity contained within Age UK's annual accounts.
It is claimed the charity had been recommending a special E.ON tariff in leaflets and booklets, stating it was "great value" and "helps save energy and money".
The charity has been paid at least £6 million every year, receiving around £41 for every person that signed up, it was reported.
It was claimed that the tariff, on average, costs pensioners £245 more than they would pay on E.ON's cheapest deal.
E.ON has confirmed there was a "commercial relationship" between it and the charity but the supplier said its tariffs were competitively priced, and Age UK has rejected any allegations of wrongdoing.
Existing E.ON customers on the tariff will be unaffected, and will be able to continue until the end of their contract or move between tariffs without penalty, the energy company said.
Customers wishing to change supplier will be able to do so without being charged.