Somerville said those receiving the payment in Scotland would be better off than their counterparts in the rest of the UK.
Around 720,000 people are expected to be eligible for the funding.
UK chancellor Rachel Reeves last week confirmed the payment would be reinstated to the majority of pensioners in England, following months of anger and protest over changes implemented last year.
Somerville said this was a “welcome, if belated” move following a “betrayal of millions of pensioners” in 2024.
The Scottish government had delayed plans for its pension age winter heating payment after the Westminster cut was announced.
But in November it announced pensioners would receive at least £100 every year.