Borders on Wikipedia.
 

Ancrum, Church of Scotland. It's dated here to 1888/90. NT 6267 2458. © Bill McKenzie. It was successor to what is today known as Old Ancrum Kirk, or Ancrum Old Parish Church, which stands further west close to the river, at NT 6215 2488. Not seen by Streetview, this source dates it to 1761-2, on the site of 12th century church, and it says it was "reduced to a romantic ruin by Sir William Scott of Ancrum" soon after the present church opened. A photo can be seen here. Category B listed. Old O.S. maps show a Free Church at NT 6291 2450. It's dated here to 1851, and maps imply it survived as an active church into the 1950's at least. It hasn't been seen by Streetview, and I haven't been able to find a photo.
Ashkirk, Church of Scotland. NT 4660 2199. © Bill McKenzie. Another view, and an interior view, both © Ina Penneyston (2011). Link. Category B listed.
Ayton, the Parish Church. Its Category A listing dates it to 1864-6. NT 9273 6087. From an old postcard in Reg Dosell's Collection. A modern view, © Steve Bulman (2017). A short distance away, still within the churchyard, stand the remains of the Old Parish Church (St. Dionysias). Little could be seen because of the ivy covering it, but some 1960's photos on the Canmore entry are more revealing, here and here. NT 9279 6095. © Steve Bulman (2017). Category B listed.

Bankend, the former Castleton Old Church (CoS). Replacing a medieval predecessor on a different site, it dates from 1808 and was closed in 1952. NY 4971 8948. © Alan Marsden (2021). Link. The site of the medieval church is marked on O.S. maps at NY 5083 8982, at the centre of a burial ground, which can be seen here in a Streetview from 2021.
Bonkyl - see Preston, below.
Bowden, Church of Scotland. NT 5543 3015. © Bill McKenzie. Link. Category B listed. The churchyard itself is also Cat. A listed. Older O.S. maps show a Free Church at NT 5552 3059. Pre-dating a map of 1898, it survived into the 1960's at least, but was demolished at some point - a bungalow now stands on the site, see here by Streetview in 2021.

Caddonfoot, Church of Scotland. NT 4507 3476. © Bill McKenzie. Another view, © Ina Penneyston (2011). Link1. Link2.
Calzeat, the Broughton, Glenholm & Kilbucho Parish Church. It's dated here to 1804, and there's an illustration of how it appeared before its spire was removed. NT 1136 3570. The former Free Church, now a museum to the writer John Buchan. It pre-dates a map surveyed in 1856. NT 1140 3562. Both © Steve Bulman (2017).
Chirnside, CoS. This source says there is some 12th century fabric, but it is mostly of an 1878 re-build, with later additions. NT 8696 5603. © Bill McKenzie. Three more views - 1, 2, 3, and the door, all © Steve Bulman (2017). Category B listed. The Chirnside Community Centre is marked on older maps as a Free Church, dated here to 1783. NT 8700 5656. © Steve Bulman (2017). Old maps also show a United Presbyterian Church, off what is now the B6355, at NT 8706 5663. This source dates it to 1857, with demolition in 1980. Its site lies under a row of houses, visible in the background above the sandstone gate pillars, in this 2021 Streetview.
Cockburnspath, St. Helen. Another view. NT 7745 7105. Both © Steve Bulman (2017). Category A listed. A former Free Church stands at the junction of Callander Place and Hoprig Road, at NT 7722 7097. It's dated here to 1890, and was seen by Streetview in 2008.
Coldingham, the remains of the Priory on High Street. The parish church occupies the choir of the Priory Church. Two further views - 1, 2, and two interiors - 1, 2. Some architectural fragments and grave covers have been assembled into a wall. NT 90390 65953. Link1. Link2. The former (and semi-derelict) United Presbyterian Church, behind the garage on the corner of School Road and Bridge Street. Pevsner dates it to 1870, and says that it was built on the site of a church of 1793. It was closed on or before 1952. NT 90210 65929. All © Steve Bulman (2017).
Coldstream.
Crailing, Ale and Teviot United Church (CoS, C). Pevsner dates it to circa 1775. NT 6821 2504. © Bill McKenzie. Another view, © Bill Henderson (2014). Link. Category B listed. The structure on its south side which I photographed in the hope that it was perhaps a previous church is described by Pevsner as a burial enclosure. © Steve Bulman (2024). Lothian Hall is the former Crailing United Free Church (20201 Streetview), dated by Pevsner to 1900-1, and the village hall since 1931. NT 6876 3473. A little over ¼ of a mile to the S.S.E. in the grounds of Crailing House is the site of a church within a burial ground. Not visible to Streetview, its Canmore entry (where there are photos of the site and monuments) says it was "dismantled in 1754". NT 6885 2427. 
Cranshaws, the Kirk, dating from 1899, though on the site of an earlier church. Its Category A listing says it was built on the site of a predecessor of 1739. NT 6923 6185. © Bill Henderson. Two more views - 1, 2, two of the interior - 1, 2, all © Steve Bulman (2017). Link. The remains of the Old Parish Church stand a little over ½ a mile to the west, at NT 6836 6167. Not visible to Streetview, some photos are available on the Canmore entry.

Denholm, Ruberslaw Parish Church (CoS), built as a Free Church in 1845. NT 5688 1849. © Bill Henderson (2014). Link. The 6" O.S. map of 1899 shows a Mission Hall off Leydens Road, at NT 5691 1859. What appears to be the same building is shown on a map of 1861, marked as Church (Congregational). From the 2009 Streetview it's not apparent that anything of it survives, but it stood where the building with the red door stands now, or perhaps a little to its rear.
Dryburgh, the Abbey Church of St. Mary the Virgin. NT 5913 3168. © Bill McKenzie. Two further views - 1, 2. Both © James Murray (2009). Douglas Haig (Earl Haig), the WWI general, is buried here, and here lies Sir Walter Scott. Both © James Murray (2009). Two old postcards show the same subjects - 1, 2, both from Christopher Skottowe's Collection. An old photo showing the font is available here. John Bowdler was trying to discover the location of the same font - clearly labelled as "The Old Celtic Font, Dryburgh Abbey", but John has searched for modern photos showing the font in situ, without success. So has the font been moved somewhere else? It does appear to have been moved, though it remains on the site - Jay Priest has found a photo of the font (labelled as basin) on this website, where there are many other photos of the Abbey. It appears to be no longer on the base in John's photo (though it seems unlikely that that base was the original). Link. Grade I listed. Other listed features associated with the Abbey can be found here.
Duns.

Earlston, the Parish Church. NT 5806 3875. © Bill McKenzie. Link. Category C listed. Older O.S. maps show a U.P. Church on High Street at NT 5774 3855. POWiS dates it here to 1792, a re-build of an earlier church of circa 1750, says that it was variously Free Church and CoS, and also known as St. John's. It was demolished in 1985. An old photo is available here. Its site was seen by Streetview in 2021. West Free Church stood near the west end of High Street, at NT 5740 3848. It's dated here to 1778, as Antiburgher, later Free, U.P., and CoS. Closed in 1887, it was long used as a church hall, later in commercial use. An old photo can be seen here, and its site in a Streetview from 2021.
Eccles, the Parish Church. Its category B listing dates it to 1774. NT 7639 4132. © Bill McKenzie. Link. The slight remains of St. Mary's Convent stand in the churchyard. According to this source, "parts of the sandstone walls remain upstanding, densely overgrown with ivy". The wall may be one seen by Streetview in 2021 - immediately to the left of the tallest grave monument. Can you confirm? The village hall is shown on older maps as a Free Church - seen here by Streetview in 2021. This source dates it to 1883. NT 7636 4144.
Eckford, CoS. NT 7062 2706. © Bill McKenzie. Link1. Link2. Category B listed.
Eddleston, the Parish Church, an 1829 church on the site of a 12th century one. NT 2440 4721. © Steve Bulman. Link. Category B listed.
Edgerston, the parish church. Its category B listing dates it to 1838. NT 6846 1171. © Bill Henderson. Evidently now closed, as it was being offered for sale in 2018.
Ednam, CoS. The category B listing dates it to 1900, but its saying "the present church" implies an earlier building, and pre-1900 maps confirm this. However, this source has it as being built in 1805, and "recast" in 1902, whatever that means. NT 7370 3716. © Bill McKenzie. Link.
Edrom, the Parish Church. NT 8276 5584. © Bill McKenzie. Two additional views - 1, 2. The Edrom Arch at the rear of the church must be what according to the The Buildings of Scotland is Logan Aisle, which it describes as a "rectangular burial enclosure .... open archway in the east wall presumed to be the re-set main doorway of the medieval church". All © Steve Bulman (2021). Category A listed.
Ettleton. The cemetery just south of Newcastleton at one time had a church, though nothing now remains to indicate its exact position. According to the Borders edition of the Buildings of Scotland, it fell into disuse circa 1604. It has spectacular views across Liddesdale. Another view. It has several fine monuments, of which this is an example. A number of fragments from the old church have been collected together. NY 4723 8632. All © Steve Bulman (2015). Link.
Ettrick, Ettrick Kirk (CoS). NT 2599 1451. © Ina Penneyston (2010). An old postcard view, from Steve Bulman's Collection. Link. Grade B listed.
Eyemouth, the Parish Church on Victoria Road and Coldingham Road. NT 94409 64050. © Bill McKenzie. Another view, © Derek Robertson. United Congregational Church on Albert Road. NT 94415 64091. © Derek Robertson. Another view, © Bill Henderson. St. Andrew (R.C.) on Victoria Road. NT 94452 64043. © Bill Henderson. The Old Parish Church (1811) on Manse Road was converted in 1981 to be the town museum and tourist information centre. NT 9454 6429. © Steve Bulman (2017). St. Ebba, off Paxton Terrace. Circa NT 9427 6438. © Steve Bulman (2017). Link.

Fogo, the parish church. NT 7725 4919. © Bill McKenzie. Link. Category A listed, wherein it says it was "predominantly rebuilt 1755".

Galashiels.
Gavinton, Langton Church. The church website dates it to 1872, on the site of a predecessor of 1798. NT 7668 5221. © Bill McKenzie. Category B listed. Old maps show a Free Church standing to the west of the village, at NT 7648 5208. It survives, converted, and was seen by Streetview in 2011. This source calls it Langton Free Presbyterian Church, and dates it to 1843. Nearby, O.S. maps show a Church (Site of) and a Chapel (Site of). The church, at NT 7624 5253, stands in a former burial ground, near Langton House, and, according to this website it was the Old Parish Church, and perhaps has some scant remains still visible. The chapel, at NT 7572 5271, is dated here to 1680, where it says some foundations remain visible. Neither site is visible on Streetview, and I've been unable to find any photos.
Greenlaw, Church of Scotland. Its very brief category A listing dates it to 1675, with later additions. It had a medieval predecessor. NT 7116 4616. © Bill Henderson. Another view, © Steve Bulman (2017). Link. Old maps show a Free Church on West High Street, at NT 7100 4602. Presumably it was this Free Church which is mentioned on Genuki as being in existence by the time of an 1866 directory. Its site was seen by Streetview in 2022. Mentioned in the same directory is a United Presbyterian Church. One shows on old maps on The Square at NT 7120 4602. It seems to be in use as a garage in 2022 (Streetview).

Hermitage, the remains of the medieval (C13/C14) chapel. Another view. Some re-erected window stonework stands against a field wall; the neighbouring Hermitage Castle stands guard nearby. NY 4933 9599. All © Steve Bulman (2012). Link. Category A listed.

Innerleithen.

Jedburgh.

Kelso.
Kilbucho - see Mitchelhill, below.
Kirk Yetholm, the Parish Church. NT 8257 2809. © Bill McKenzie. Link. Category B listed, wherein it's dated to 1835-7.
Kirkton, the Parish Church (CoS). It's dated here to 1841, where it says that it replaced an earlier church "probably on the same site". NT 5403 1395. © Bill Henderson. Category C listed. A 2022 news report says that it was closed in 2014, and it was to be converted into a house.

Ladykirk, Church of Scotland. NT 8888 4766. Two additional views - 1, 2, two of the interior - 1, 2, and the font, all © Steve Bulman (2021). Link. Grade A listed.
Lauder, St. Mary (CoS, 1673). Another view, and three of the interior - 1, 2, 3. NT 5309 4754. All © Steve Bulman (2019). Link1. Link2. Link3. Category A listed. Older O.S. maps show two other churches. A United Presbyterian Church stood on West High Street at NT 5279 4778. It pre-dated a map of 1862, and survived into the 1960's at least. Demolished at some point, its site was seen by Streetview in 2021. The other was a Free Church, set back from the north side of High Street on Kirk Wynd and Castle Wynd, at NT 6318 4759. It is presumably the same building which now serves as the parish church hall, which was seen by Streetview in 2021. It also pre-dates the 1862 map, and had ceased to be active by the time of a map of 1962.
Legerwood, Church of Scotland. NT 5940 4342. © James Denham (2010). Link. Category A listed.
Lennel, the remains of the medieval Old Parish Church. Two more views - 1, 2. NT 8575 4117. All © Steve Bulman (2017). Canmore entry. Category B listed.
Lilliesleaf, CoS. NT 5391 2531. © Bill McKenzie. Link1. Link2 dates it to 1771. Category B listed. O.S. maps mark Burial Vaults and remains of Church in the churchyard to the south-east of the present church - presumably a predecessor. The remains aren't visible on Streetview. The churchyard, including these remains, is category B listed. A little over half a mile E.N.E. of the church is a cluster of buildings (Chapel Farm), one of which is labelled Chapel on O.S. maps. Aerial views suggest it survives, but it isn't visible on Streetview, and I haven't been able to discover anything about it, other than a brief news report about the discovery of an old skeleton. NT 5475 2563. A map of 1921 shows a United Free Church south of the main road through the village, at NT 5358 2518. What appears to be the same building is present but not labelled as a place of worship on a map of 1899 - the same applies to a map of 1963. The building survives - presumably converted to residential use -  and was seen by the Streetview van in 2021, from a street running parallel to the main street (from where the church is screened by dense vegetation).
Lyne, Church of Scotland. NT 1918 4052. © James Denham (2010). Link. Category B listed.

Melrose.
Minto, the Parish Church (CoS), was completed in 1831 as part of the planned village designed for the 2nd Earl of Minto. There was an earlier medieval church nearby which this one replaced. NT 5668 2013. © Robert Tofts. Link1. Link2. Category B listed. The earlier church stood less than half a mile to the E.N.E., at NT 5720 2031. Older O.S. maps label it as Church (Remains of), but this source says that nothing of the church survives. Another source implies some remains, and has a number of photos of gravestones. Also see here. The site hasn't been seen by Streetview.
Mitchelhill, the ruins of Kilbucho Church. Medieval, this source says it "was abandoned some time after 1810". NT 0654 3375. © Tim Tomlinson.

Newcastleton, the Parish Church (CoS, 1888) on Montagu Street. NY 4819 8766. © Steve Bulman (2012). Link. The former Burgher Church (1804), now a heritage centre. Older O.S. maps label it as U.P. Church. NY 4817 8721. © Steve Bulman (2012). Two other churches show in the town on older O.S. maps. A Free Church stood on Langholm Street at NY 4823 8758. It now serves as the village hall, and was seen by Streetview in 2021. It has date-stones for 1853 and 1956, the latter perhaps for when it became the hall. Link. The other one is marked as E.U. Church and still stands on South Hermitage Street at NY 4828 8750. This source advises that it was originally Congregational, and dates it to 1850. Streetview saw it in 2021. The former Castleton Parish Church stands about 1½ miles to the N.E., at NY 4971 8948. Seen by Streetview in 2021, when it appeared to be undergoing conversion to residential use. Link, wherein it's dated to 1808. Category B listed. Its predecessor, St. Martin, stood about ¾ of a mile to the E.N.E. at NY 5084 8981. It was demolished in 1808 and the masonry removed to allow the building of Castleton Parish Church (source). It stood in a substantial graveyard, which survives - it was seen by Streetview in 2021.
Newtown St. Boswells (including St. Boswell's), Newtown Church (CoS) - marked on older maps as U.P. Church. NT 5805 3152. © Bill McKenzie. Link. Category C listed, wherein it's dated to 1867. The Old Parish Church stands on the banks of the River Tweed, to the S.E. of the town, at NT 6063 3053. This source says that only the foundations remain, located within a graveyard - seen here by Streetview in 2021. It also says that this church is reputed to have had two predecessors, on different sites, but doesn't locate them. Old maps show a Free Church in the town on what is today the B6404 at NT 5942 3102. Now the parish church, it's dated here to 1844. Streetview saw it in 2016. St. Columba's College has a Chapel, mentioned here. Not seen by Streetview, a photo is available here (scroll down). NT 5867 3187. The school may no longer exist, as a news article from 1993 discusses its proposed closure. Do the buildings survive?

Paxton, Church of Scotland (1907). Its category C listing dates it to 1908. NT 9342 5306. © Bill Henderson (2012). Link says it used to be United Free.
Peebles.
Polwarth, the former Church of Scotland, sold in 2006 (thanks to Jim Napier). It's dated here to 1703, and had at least three predecessors. Another view. NT 7800 4949. Both © Bill McKenzie (2013). Link. Category A listed.
Preston, Bonkyl Kirk (CoS), which stands about 2 miles distant from the village at NT 8086 5960, was built in 1820. © Bill McKenzie (2013). Another view. A list of Ministers "since the Reformation" hangs inside the entrance lobby. Unfortunately the entrance to the church proper was locked on both of my visits. The surviving apse from its medieval predecessor stands adjacent. Another view. All © Steve Bulman (2017 and 2021). Link. Grade B listed.

Reston, Church of Scotland. The church website dates it to 1880, as a Free Church. Another view. NT 8785 6210. Both © Steve Bulman (2021). Grade C listed.
Roxburgh, the Parish Church, dated here to 1752, "probably on the site of an earlier church". NT 7001 3069. © Bill McKenzie. Category B listed.

St. Abb's. NT 91721 67368. © Bill McKenzie. Two additional views - 1, 2, both © Steve Bulman (2017). Link, which advises that it opened in 1891 as St. Abb's Free Church, and closed before 2011.
St. Boswell's - see Newtown St. Boswell's, above.
Saughtree, Liddesdale Parish Church, dated here to 1872. NY 5611 9682. © Bill McKenzie (2010).
Selkirk.
Skirling, the Parish Church (1720, CoS). The bellcote has a sun-dial beneath. NT 0752 3900. Link. Category B listed. A former Free Church (now residential) stands nearby at NT 0757 3916. The very brief category C listing dates it to circa 1846. All © Steve Bulman (2013).
Smailholm, the Parish Church. Another view. The church notice board had pinned to it a newspaper clipping discussing the planned conversion into a residence. NT 6487 3641. Both © Steve Bulman (2024). Its Canmore entry has numerous photos. Link. Category B listed. Older large scale O.S. maps mark, at NT 6401 3400 "F.C. Meeting House". Aerial views show that it no longer exists, and its site hasn't been seen by Streetview - access to it was down this path (2023 Streetview) on the right. I assume this to be Free Church Meeting House, but it isn't marked as a place of worship. Can you advise what this was?
Sprouston, the Parish Church. NT 7566 3532. © Alan Blacklock. Link. Category B listed, wherein it's dated to 1781.
Stichill, Church of Scotland. NT 7111 3828. © Bill McKenzie. An interior photo can be seen here. Link. Category B listed. A former U.P. Church stands a little way to the N.E. at NT 7132 3843. Seen by Streetview in 2021, Canmore dates it to 1877, and "disused in 1994".
Stobo, the Kirk, reputedly of C6 foundation. NT 1828 3765. © Steve Bulman. Link. Category A listed.
Stow, the ruinous Old Parish Church. NT 4592 4456. © Tom McLean. Another view, © Bill Henderson. Its Canmore entry has more photos. Category B listed. The demolished United Free Church (and earlier United Presbyterian). NT 4598 4475. From an old postcard in Steve Bulman's Collection. In the background of that postcard can also be seen St. Mary of Wedale (1873-6), better seen by Streetview in 2022. NT 4590 4437. Link. Category B listed.
Swinton, the former Free Church, dated here to 1866. NT 8353 4748. © Bill McKenzie. The Parish Church. This source dates it to 1729, on an ancient site. NT 8387 4764. © Steve Bulman. Another view, © Bill Henderson (2012). Category B listed. According to this source, the property known as Fiddler's Ha' (10, Coldstream Road) is a former Free Church of 1843. No available maps show it, but Streetview saw the property in 2021. NT 8389 4749.

Traquair, the Parish Church, also known as Kirkbride. NT 3200 3346. © Steve Bulman. Link. Category B listed. Traquair House, which stands almost a mile and a half to the N.N.E. of the church, has its own Catholic place of worship, variously described as Chapel or Oratory. Not visible on Streetview, I haven't been able to find an exterior photo, but there are several of the interior here, where it's dated to 1829. NT 3305 3552. Link. Mentioned here and here is a possible precursor of the parish church standing in a lonely spot S.W. of the present church, at NT 3140 3290. The site, if such it is, hasn't been visited by the Streetview van.
Tushielaw, the former Tushielaw Free Church, which has been disused for decades. My appreciation to Janet Gimber for the identification. NT 3035 1778. © James Murray (2009). Two additional views - 1, 2, both © Howard Richter (2013). The church must post-date 1893, since neither it, nor the adjacent manse appear on the OS map of that year. Both are shown on the edition of 1924. Strangely, Pevsner gives the date as "mid C-19". Link.
Tweedsmuir, the parish kirk (1874). NT 1007 2453. © Steve Bulman. Another view, © John Cannon. Link1. Link2. Grade B listed.

Upsettlington, the site of the vanished Convent Chapel (somewhere in the field). O.S. maps mark the site of a chapel at NT 8872 4684. Pevsner mentions (in the Ladykirk entry) that the predecessor of Ladykirk had been a chapel at Easter Upsettlington, since at least as far back as the 13th century. Link.

Walkerburn, the Parish Church. NT 3640 3724. © Steve Bulman. Its category B listing dates it to 1875, with subsequent enlargement. Its Canmore entry has more photos, including the interior. O.S. maps show a Congregational Chapel almost immediately opposite the previous church, at NT 3640 3719. It pre-dates a map of 1898. A building certainly survives there, but rampant undergrowth prevents a good enough view to decide if it's the church - Streetview 2022.
Whitsome, the former Whitsome Kirk, as seen by Streetview in 2021. This source dates it to 1803, and says it was in "full ecclesiastical use" in 2003. The Streetview suggests it may now be closed and converted - or has it just recently had a refurbishment? NT 8604 5049. Category C listed. The Old Parish Church ruin stands in a graveyard to the S.E. of the church, at NT 8623 5034. What, if anything survives of the church itself is unclear from on-line sources. Large scale O.S. maps mark only a Watch House, presumably against the depredations of the "Resurrection Men", but this could of course still have been part of the church. This source, discussing Whitsome Old Parish Church Site says "This is a 13th century church ruin...". Its Canmore entry includes some photos of the watch house, but doesn't say if it's part of the former church. Here's a distant Streetview of the churchyard and watch house in 2021.

Yetholm, the Kirk Yetholm Parish Church. It's dated here to 1837. NT 8257 2809. © Steve Bulman. Link. Category B listed.