Big Six mortgage rates were consistently the most expensive options available to Canadians throughout 2018, according to new data.

LowestRates.ca, an online recommendation site for personal finance products such as mortgages, loans, credit cards and insurance, found that the lowest posted rates offered by the Big Six banks were always more costly than the lowest rates available from smaller lenders.

"The big banks never offer the lowest posted rates on the market, but Canadians aren't spending enough time researching rates before signing their mortgages, and that's potentially costing them thousands of dollars a year," said Justin Thouin, CEO and co-founder of LowestRates.ca.

Mortgage rates fluctuate based on the rates at which lenders, such as banks and brokers, borrow money – they often borrow money to ensure they can meet the demands of consumers requiring mortgages. If the rates they borrow at fall, the rates that consumers borrow at should fall in conjunction. With big banks, however, this is often not the case.

"Brokers and smaller lenders often drop their rates first to be more competitive, and banks are slower to implement changes because they know they own the market," Thouin said. "This will only change when Canadians realize they're being overcharged and begin to shift away from the banks, and that will only happen as we increase awareness about the alternative market.”

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