Mainland on Wikipedia.

Aith, Church of Scotland. © Tim Flitcroft (2012).

Bigton, Church of Scotland. © Tim Flitcroft (2012).
Brae, the Kirk (CoS). Gospel Hall. Both © Tim Flitcroft (2012).
Braehoulland, the former Church of Scotland, now in residential use. It originally dates from 1895 as United Presbyterian. Following the move of the then CoS congregation to join with that of the Eshaness Free Church (see below) in 1929, Braehoulland was used as a public hall for several decades. HU 2402 7947. © Alan Marsden (2021).

Cloddiknowe, Gospel Hall. © Tim Flitcroft (2012).
Clousta, the former United Free Church. HU 3132 7570. © Alan Marsden (2024).
Culswick, Methodist Church. Another view, and an interior view. All © Tim Flitcroft (2012).
Cunningsburgh, Church of Scotland. United Free Church (1844). The former Mail Kirk. Link. All © Tim Flitcroft (2012).

Dale of Walls, the former Gospel Hall. © Kevin Price (2011).
Dunrossness, the parish church. Baptist Church. Both © Martin Briscoe. The former Methodist Church. © Tim Flitcroft (2013).

Eshaness, the former United Free Church (CoS from 1929) is now a Public Hall, and dates from circa 1871 (source). HU 2372 7851. © Alan Marsden (2021).

Gillaburn, the former Wesleyan Methodist Chapel (according to O.S. maps) or non-denominational chapel according to this source which dates it to circa 1872 to the 1960's. The chapel was used once more in about 2005 - see the "Quakers" section for the story. HU 4061 5148. © Alan Marsden (2021).
Girlsta, Methodist Church. © Tim Flitcroft (2012). Link.
Gonfirth, Methodist Church. © Tim Flitcroft (2012). Link.
Gruting, Methodist Church. Another view, and three interior views - 1, 2, 3. All © Tim Flitcroft (2012).
Gulberwick, Church of Scotland (1898). © Tim Flitcroft (2012). Link.

Hillswick, Church of Scotland. © Tim Flitcroft (2012).
Hoswick, former Gospel Hall. © Tim Flitcroft (2012).

Ireland, Methodist Church. © Tim Flitcroft (2012).

Lerwick.
Levenwick, Mission Hall (Methodist). © Tim Flitcroft (2013).
Lunna, St. Margaret (Church of Scotland). Interior view. Both © Tim Flitcroft (2012). Link

Mid Walls, Church of Scotland. Appeared derelict in 2011. © Kevin Price (2011).
Mossbank, Church of Scotland. © Kevin Price (2011).

Nesting, Church of Scotland. HU 487 578. © Susan Sinclair. Another view, © Kevin Price (2011). Methodist Chapel. © Kevin Price (2011).
North Roe, Church of Scotland. Another view, and an interior view. Methodist Church. Link. All © Tim Flitcroft (2012).

Ollaberry, Church of Scotland. The former United Free Church. Both © Tim Flitcroft (2012).
Orgill, the former Lunnasting Baptist Church. Closed in 1997, it was converted to residential use about 15 years later. HU 4819 6507. © Alan Marsden (2021).

Quarff, Church of Scotland. It's dated here to 1828-9, where it also says that in 1993 it was "reported to have been disused for some time". HU 4285 3547. © Tim Flitcroft (2012). After the previous church closed, what had been a Free Church (so named on a map of 1901) was used by the CoS, but that too closed and the building is now in residential use. Another view. HU 4279 3575. Both © Alan Marsden (2024).

Reawick, Congregational Church. © Tim Flitcroft (2012).

Sand, Church of Scotland. Interior view. Baptist Church. All © Tim Flitcroft (2012). The former Sand Congregational Church (now derelict). Another view, and the interior. All © Kevin Price (2017).
Sandness, the Parish Church (CoS). It's marked on older maps as Free Church. HU 1962 5714. © Kevin Price (2011). Methodist Church at Norby. Another view. © Kevin Price (2011). Just a little way to the south O.S. maps mark St. Ninian's Chapel (Site of), at HU 1993 5738. It's featureless site can be seen here in the middle distance, on a Streetview from 2009. The former St. Margaret at Melby. HU 1912 5766. © Kevin Price (2011). The former Congregational Church, also at Melby. Dating from circa 1832, even before a map of 1902 it had been converted into a post office, and it's now residential. HU 1920 5759. © Alan Marsden (2021).
Sandwick, Church of Scotland. Link. Grade B listed. United Free Church. The former Wesleyan Chapel. All © Tim Flitcroft (2012).
Scalloway, Church of Scotland. The former United Presbyterian Church on the junction of Castle Street and New Road. Both © Martin Briscoe. Gospel Hall, © Tim Flitcroft (2012). Methodist Church, © Tim Flitcroft (2012). Link. The former Congregational Church (1838), © Tim Flitcroft (2016). The former Exclusive Brethren Meeting Room on Hillside Road. © Tim Flitcroft (2016).
Selivoe, Gospel Hall. © Tim Flitcroft (2012).
Semblister, the derelict Church of Scotland. Another view, the pulpit and gallery. All © Tim Flitcroft (2013).
Sullom, Church of Scotland. Another view. Both © Tim Flitcroft (2013).

Tingwall. © Martin Briscoe. Kingdom Hall of Jehovah's Witnesses, © Tim Flitcroft (2012).
Tresta, Methodist Church. © Tim Flitcroft (2012). The former Glanton Brethren Meeting Room, now in secular use. © Tim Flitcroft (2016).
Twatt, former church. © Tim Flitcroft (2012).

Vidlin, Methodist Church, and an interior view, both © Tim Flitcroft (2012). Link.
Voe (near Tagon), the ruins of Olnafirth Kirk (1714). Voe Kirk (CoS). Another view. All © Tim Flitcroft (2012).

Walls, St. Paul (CoS). Another view. Methodist Church. Link. All © Tim Flitcroft (2012). The former Congregational Church, now a private residence. © Tim Flitcroft (2013).
Weisdale, the Kirk (CoS, 1863). Grade B listed - link. © Tim Flitcroft (2012).
West Burrafirth, the Kirk. © Tim Flitcroft (2012).
Westerskeld, Methodist Church. Interior view. Both © Tim Flitcroft (2012).
Whiteness, the former Church of Scotland. Another view. Circa HU 394 474. The former Gospel Hall. The Methodist Church, and an interior view. All © Tim Flitcroft (2012 and 2016).
Wormadale, the former Congregational Chapel. Dating from 1851, it's now in secular use. HU 3956 4636. © Alan Marsden (2021).