The yacht, which first hit the water in February achieved the expected maximum speed of 19 knots and a "smooth driving behaviour".
The shipyard said the sea trials marked a "key milestone in its path towards becoming one of the prominent brands in the world."
The yacht hit the water at a private launch ceremony at the Bilgin Yachts West Istanbul Marina in February.
The yacht is now the joint longest superyacht built in Turkey, tied with the 80 metre superyacht Elements, that was built by Turkish yard Yachtley in 2018.
The Bilgin 263 has a slim, sleek exterior profile with multiple outdoor entertaining areas, such as a huge foredeck lounge with dining area and settees. Another lounge forward of the pilothouse boasts a superyacht spa pool, offering privacy while at port.
Accommodation is for up to 16 guests split between eight staterooms, including a master suite, three VIPs and four double cabins. Meanwhile, the crew quarters allows for a staff of up to 24 people.
The yacht was sold to a three-time repeat Bilgin client in October 2015 and construction began in March 2016.
Chief executive and founder of Unique Yacht Design, Emrecan Özgün, described Tatiana as a "trendsetter among steel-aluminium superyachts of today."
He added: "With her design and comfort elements, the Bilgin 263 is truly one-of-a-kind. We created a very attractive yacht with a sleek and sexy profile while avoiding high dosage design clichés."
This 1,600GT yacht will be IMO Tier III compliant, and is predicted to reach a top speed of 20 knots, courtesy of twin 2,625hp MTU 16V4000 M73 diesel engines, while the total fuel capacity of 155,000 litres allows for a range of 5,000 nautical miles when cruising at 12 knots.
The new 80 metre yacht is the first of three 80 metre superyachts under construction at the Turkish yard.
The second Bilgin 263, which is already sold, will be launched in 2021 while the third will be delivered in 2021.