has rolled out the industry's lowest mortgage rate for investors at 1.99%.

The interest rate is available as an introductory rate under the Smart Booster Investor product. Investors with a 20% deposit or more are eligible for the discounted rate, which is available for principal-and-interest (PI) or interest-only (IO) payments terms.

The rate is being offered as a bundle for the previously launched Smart Booster Home Loan, which also has a discounted variable rate at 1.99%. This means that for investors to be eligible for the product, they have to also avail the owner-occupied rate through a new application or refinancing.

"This is the lowest investment loan rate offer in Australia right now," said Marie Mortimer, managing director at "Investors who are considering switching to a lower rate for their investment properties and their own home should take the opportunity to reassess their loan provider and potentially refinance."

Both PI and IO options of the loan revert to a rate of 2.74% after one year. The owner-occupied rate, on the other hand, rolls over to 2.48%.

Investors should always look beyond the headline rates when shopping for home loans, said Sarah Megginson, managing editor of Your Mortgage, Your Investment Property, and Australian Broker.

"A low rate is fantastic, but what if their turnaround times have blown out to three months? Or, it might be the case that once you add in package fees, account-keeping fees and other charges, the loan costs you more in the long run than a mortgage starting with a 2," she said.

Megginson said this makes it essential, even for investors, to work with a mortgage broker. With an array of products available for borrowers, Megginson said it is best to narrow down options.

"Right now, working with a broker is the key to ending up with a product and rate that suits your need," she said.

The low-interest rate environment is making the housing market more accessible for home buyers and investors, said Shane Oliver, chief economist at AMP Capital, in a recent analysis.

"Low mortgage costs also make the funding costs for an investment property very low," he said.

Oliver said support measures from the government provide a substantial boost to household income, helping prevent a material increase in mortgage delinquencies and forced sales.