Singapore Airlines travellers will soon have access to 23 new destinations in 11 countries, including Turkey, Bulgaria, Portugal and Ghana.
In a tie-up with Turkey's national carrier, SIA customers will be able to hop onto flights operated by Turkish Airlines - both domestically in Turkey and internationally.
The services will co-carry SIA flight numbers.
Turkish Airlines will similarly add its code to SIA flights from Changi Airport to five cities in Australia, two points in New Zealand as well as to Brunei and Hanoi.
The deal takes effect from May 1, subject to regulatory approval on both sides.
With intensifying competition putting pressure on profits, such partnerships are a key part of SIA's strategy to grow its network without having to launch its own new flights.
SIA now has code-share ties with 25 airlines, offering its customers nearly 3,000 weekly round-trip flights - around four times the number of weekly round-trip flights operated solely by SIA.
SIA chief executive Goh Choon Phong said recently: "These arrangements enable us in some cases to extend our network to points that are not commercially viable to serve with our own aircraft, and in other cases, to offer additional travel windows on existing routes to our customers."
Mr Ahmet Bolat, Turkish Airlines' chief investment and technology officer, said: "It is an example of Turkish Airlines' target to maximise the travel opportunities offered to passengers through the extensive networks of both airlines."
Other initiatives to grow SIA's business have included taking stakes in other carriers - the most significant being its stake of almost 20 per cent in Virgin Australia.
A new joint-venture carrier in New Delhi with India's conglomerate Tata is expected to take to the skies later this year. SIA will own 49 per cent of the yet-to-be-named entity.
Regular traveller Amy Lee, 29, a human resource executive, said: "Travellers are more adventurous these days and keen to explore new exotic places in Eastern and Central Europe, and Africa, for example. It does not make sense for an airline to fly everywhere, so the alternative is to join hands with other carriers."