This is because the Government warns there are some situations in which paying historic contributions would not boost a state pension at all.
An example might be for those who fall short of a full state pension due to being contracted out.
Sir Steve Webb, LCP partner and former pensions minister, said: “For many people, paying voluntary NI contributions can be great value for money and can help them boost their state pension in a cost-effective way.
“For people with gaps in their NI record going back more than six years, the window to fill those gaps will soon close.