The service will initially launch in Glasgow, but will be rolled out thereafter to Edinburgh and then the rest of Scotland.
Though a number of web competitors already offer a similar service, 5pm chairman and co-founder Charles Shaw said the firm's existing base of roughly 180,000 registered users should give it a strong position in the market.
"We have a large and loyal following, and that is basically what we are basing our thoughts and planning on," he said.
The takeaway venture follows a busy year for 5pm, which was set up a decade ago to provide discounted last-minute dining reservations.
New services in recent months include the launch of a health and beauty section, a gift voucher section and the introduction last week of 5pm's "Big Deal" offer.
The latter operates in a similar fashion to the "Deal of the Day" run by Groupon of the US, which gives subscribers discounts of between 50 and 90 per cent at retail, dining and leisure outlets.
5pm's expansion follows a 100,000 upgrade to its platform technology that has given the company what Shaw described as an "enormous" amount of additional capacity and flexibility. More staff will be hired, taking the total number at the Glasgow-based firm to more than 20.
Shaw said the business had performed well this year, with bookings likely to be up by between 18 and 20 per cent. "Our users still want to go out, but they are looking for a deal," he said. "We are the conduit between what the consumer is looking for and what the restaurateur is willing to offer."