Brits saved an estimated £75.5bn ($98bn) during lockdown but missed out on millions in returns.
Some 73% of people used lockdown as an opportunity to put money aside, saving on average £1,974 each, due to staying home and shopping less, saving on commuting and not buying lunch out at work.
Millennials saved the most out of all reported age groups — averaging £2,200 each.
Half of savers are putting their spare cash into instant savings accounts to access it when they need it, according to a report by Atom bank.
But despite this epic savings haul, Brits will only pocket £1.94 each in interest on average because most banks offer minimal interest on their savings accounts at just 0.01%
And more than one in 10 savers think they are set to lose money with possible negative interest rates.
After the latest rate cut, the current average interest rate on savings accounts across the big six high street banks stands at just 0.01%.
WATCH: What are negative interest rates?
The report also revealed that 62% of people view savings accounts as a place to safeguard money to prevent overspending whereas just 21% think they are a genuine investment opportunity.
Almost half of respondents said they would describe the state of interest rates as bad and 13% described them as terrible.
Despite the pandemic, people remain largely confident about both their short and long-term financial futures. Just under half report feeling confident about money in the short-term, with almost one in five saying they are very confident.
And when it comes to long-term financial future, over two fifths say they are confident, with 14% very confident.
Millennials are the most likely out of any age group to feel confident about both their short-term financial future (62%) and long-term financial future (55%).
Mark Mullen, CEO of Atom bank, said: “Brits have saved millions with little return for their efforts. People are even stockpiling cash in their homes rather than in a bank account, which shows just how little they think they’ll gain by trusting the big six with their money.”