Balta Sound is a sound (inlet) on the east coast of the island of Unst in the Shetland Islands, Scotland. The sound is sheltered from the North Sea to the east by the uninhabited island of Balta.

The settlement at the west of the sound is Baltasound.

On 12 March 1917, the World War I British E-class submarine HMS E49 was heading out of Balta Sound on patrol when it struck a naval mine laid by German U-boat SM UC-76. It was sunk in the channel between the islands of Huney and Balta with the loss of the entire crew. The site of the wreck is now designated as a war grave.

60°45′18″N 0°50′24″W / 60.75500°N 0.84000°W / 60.75500; -0.84000

v t e Shetland
Inhabited islands	Mainland Bressay Burra East Burra West Burra Fair Isle Fetlar Foula Muckle Roe North Isles Out Skerries Papa Stour Trondra Unst Vaila Whalsay Yell
Other islands	Balta Bigga Brother Isle Colsay Hascosay Hildasay Lamba Linga, Bluemull Sound Linga, Busta Voe Linga (near Vementry) Linga, Vaila Sound Linga, Yell Sound Mousa Noss Oxna Papa Papa Little Samphrey South Havra St Ninian's Isle Uyea, Northmavine Uyea, Unst Vementry Ve Skerries West Linga
Towns and villages	Lerwick Aith Baltasound Bigton Bixter Brae Cunningsburgh Grutness Gulberwick Gutcher Haroldswick Hillswick Levenwick Mid Yell Mossbank North Roe Ollaberry Quarff Sandwick Scalloway Symbister Toab Toft Ulsta Uyeasound Vidlin Voe Walls Weisdale Whiteness
Mainland Parishes	Delting Dunrossness Lerwick Nesting Northmavine Sandsting Tingwall Walls and Sandness
Insular Parishes	Bressay Fetlar Unst Yell
Maritime features	Balta Sound Bluemull Sound Burra Voe Busta Voe Calder's Geo Ronas Voe St Magnus Bay Sullom Voe West Voe of Sumburgh Yell Sound
Extreme points (N S E W)	Out Stack The Skerry, off Fair Isle Bound Skerry Waster Hoevda, Foula
Topics	Animal breeds Etymology History Prehistory