At 65% fixed for two years, direct consumers can access a rate of 1.63% with an arrangement fee of £1,995 or 1.88% up to 75% with a fee of £1,495.
This compares to 1.98% at 75% with a fee of £995 available to brokers which can also be accessed in-branch.
At 90% in-branch consumers have a choice of two three-year fixed rates at 3.99% with a fee of £995 and 4.45% fee-free compared to 4.55% fee-free offered to brokers.
The direct-only five-year fixed rate product is 0.30% lower than the broker alternative at 4.95% – both carry no arrangement fee.
The Post Office described the move as a ‘fresh challenge’ to the mortgage market.
On Monday the Post Office launched its broker product range available through Legal & General Mortgage Club.