"We want to assist new and existing members the best we possibly can during these challenging times."
A two-year fixed rate is available at 2.79% and a five-year fix starts from 2.99%.
The products are available for residential purchase, remortgage or rate switch.
The Society has also launched new products at 75% LTV, including a two-year fixed rate at 1.75% and a five-year fix at 1.95%.
All products have no product fee and a maximum loan size of £750,000.
Last week, a number of lenders temporarily suspended their higher-LTV mortgage products due to high demand, including Accord Mortgages, Ipswich Building Society, Clydesdale Bank and Virgin Money.
Coventry for intermediaries later launched a limited tranche of 90% LTV products which closed at end of play yesterday.
Dan Goulding, product development manager at Monmouthshire BS, said: “We want to assist new and existing members the best we possibly can during these challenging times.
“We know from broker feedback that the lockdown has provided people with more time to think about their living arrangements, and we feel this extended range will help first-time buyers and also people who already have a mortgage.”
