On 18 December, MPs are launching an inquiry into how changes to the Winter Fuel Payment are affecting pensioner poverty.
Before the chancellor's announcement on 29 July, the average number of weekly applications in the UK for Pension Credit, where the government tops up a pensioner's income, was 3,800.
Since August, it's been averaging around 9,400 following campaigns by the government and charities, encouraging people to claim.
DWP data shows that in the week of 18 November, the average processing time for a Pension Credit application was 65 working days, or 13 weeks, up from 9 weeks at the end of July.
That average processing time, unless it has picked up, would mean eligible people who submitted an application in November or December would likely not receive their £200 to £300 Winter Fuel Payment - and backdated Pension Credit payment - until February or March 2025.
The former pensions minister, Steve Webb, who is now a partner at pension consultants LCP said: "Although they will eventually receive arrears once Pension Credit comes into payment, including any Winter Fuel Payment to which they would have been entitled, most who were on the waiting list by mid November are likely to have to manage through Christmas and the New Year on a very modest income until their claim is processed".
A government spokesperson said: "Over a million pensioners will still receive the Winter Fuel Payment, and our drive to boost Pension Credit take up has seen applications more than double with over 40,000 more pensioners now receiving it, as well as the Winter Fuel Payment."
"We have deployed additional staff to support processing applications, seeing a 51% increase in the number of cleared claims since the Chancellor's announcement."
The Scottish government has announced that from late 2025 every Scottish pensioner household will receive a winter fuel payment.
The numbers in the UK at risk of delayed payments this year are uncertain because it depends on the rate at which DWP officials are working through the backlog.
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