Northumberland on Wikipedia.

Acklington, St. John the Divine. 81 NU 227 019. © Steve Bulman.
Allendale.
Alnmouth, St. John the Baptist. © David Gallimore. Link. Methodist Church, founded as Wesleyan in 1891. © Peter Morgan (2009). Two further views - 1, 2. Both © David Gallimore (2009). Hanwick Hall, which Peter advises is "thought to have been Methodist". The same building can be seen from the other side in this old photo. Notwithstanding this, I can find no web text reference to Hanwick Hall, so can you confirm that it was indeed a Methodist Chapel? © Peter Morgan (2009). David Gallimore has sent a photo of Hindmarsh Hall, which is evidently the same building as Hanwick Hall. Previously a granary and corn exchange, it was converted to serve as a church in 1859, in which use it continued until 1876 when St. John was opened. © David Gallimore. Link.
Alnwick.
Amble, St. Cuthbert. © Bill Henderson. All that remains of the cemetery buildings is this arch, which used to have a chapel to either side. These were demolished in 1971. © Peter Morgan (2009). Sacred Heart & St. Cuthbert (R.C.). © Peter Morgan (2009). St. Mark (U.R.C. formerly Congregational). © Peter Morgan (2009). Trinity Methodist Church. © Peter Morgan (2009).

Bamburgh, St. Aidan, whose graveyard contains Grace Darling's grave. Both © Bill Henderson. Two interior views - 1, 2. Both © Peter Morgan (2009). Two further views - 1, 2, and an interior view, all © David Gallimore (2009).The remains of the Chapel of St. Peter, within Bamburgh Castle. The apse. Both © Steve Bulman.
Beadnell, St. Ebba. © Peter Morgan. Two further views - 1, 2, both © David Gallimore (2009).
Belford, St. Mary. © Bill Henderson.
Bellingham, Methodist Church. NY 839 833. © Bill Henderson.
Berwick-upon-Tweed.
Birdhope Craig, Scotch Church (closed since about 2006). Another view. NY 828 982. Although the plaque says 1826, Tony has a family baptism here from 1824, so this probably isn't the first building on the site. Both Anthony Preston.
Blanchland, the Abbey of God and St. Mary the Virgin, or just St. Mary the Virgin. © Bill Henderson. Link. Another view, and an interior view, both © Peter Morgan (2009).
Blyth.
Bolton, a chapel whose mother church is Edlingham, St. John the Baptist. © Susan Sinclair.
Bothal, St. Andrew. © Sally Funk.
Boulmer, St. Andrew the Fisherman. Another view. Both © Peter Morgan (2009).
Branxton, St. Paul - the burial site of the fallen from the Battle of Flodden Field, 1513. © Bill Henderson.
Brinkburn, Brinkburn Priory. Another view. NZ 118 983. Both © Alan Hopkins. Link1. Link2.
Byrness, St. Francis. © Bill Henderson. Link.
Bywell, St. Peter. © Bill Henderson. Another view. © Peter Morgan. Link. Close by is the redundant church of St. Andrew, which is cared for by the Churches Conservation Trust. © Bill Henderson. Another view. © Peter Morgan. Link.

Capheaton, United Methodist Free Church. © Peter Morgan (2009).
Carham, St. Cuthbert. From an old postcard in Reg Dosell's Collection.
Chatton, Holy Cross Church (U.R.C.). 75 NU 056 282. © Steve Bulman. Link.
Chillingham, St. Peter. You shouldn't need a reason to visit the beautiful county of Northumberland, but here's one - the Grey Tomb. 75 NU 063 259. Both © Steve Bulman. Link.
Chollerford, , St. Giles. Interior view. Both © Peter Morgan (2009).
Corbridge.
Cornhill-on-Tweed, St. Helen. © Bill Henderson.
Corsenside, St. Cuthbert. © Bill Henderson. Link.
Cowpen, St. Cuthbert (R.C.). © Bill Henderson.
Cramlington, St. Nicholas. © Bill Henderson.

Dilston, St. Mary's Chapel at Dilston Hall. © Bill Henderson. Link.
Doddington, St. Mary & St. Michael. © Bill Henderson.

Earsdon, St. Alban. © Bill Henderson.  Another view. © Alan Craxford. Link1. Link2. Link3.
Eglingham, St. Maurice. 81 NU 106 195. © Steve Bulman.
Elsdon, St. Cuthbert. © Bill McKenzie. Another view. © Bill Henderson.
Embleton, Holy Trinity. Interior view, both © Peter Morgan (2009). Two further views - 1, 2, and another interior view, all © David Gallimore (2009).

Farne Islands (Inner Farne), St. Cuthbert's Chapel. © Peter Morgan (2009). Link.
Felton, St. Michael and All Angels. © Bill Henderson. Link. U.R.C. 81 NU 179 003. © Steve Bulman. Another view. © Bill Henderson.
Ford, St. Michael & All Angels, in the grounds of the castle. Another view. Both © Bill McKenzie.

Glanton, St. Andrew, Anglican and U.R.C. On a visit in 2008, I could only find this one church, despite the OS map showing two. Also, Pevsner (revised edition, 2001) lists only the U.R.C. church, originally Presbyterian, but doesn't give it a dedication. GENUKI lists a St. Peter, but this Glanton newsletter from 2005 mentions the up-coming closure of this church. Presumably St. Peter has been demolished, and the now combined CoE and U.R.C. was re-named St. Andrew after 2005. Unless you know better.....   © Steve Bulman.

Greenhead, dedicated to St. Cuthbert. © Steve Bulman. 86 NY 660 653.

Haltwhistle, dedicated as the Church of the Holy Cross. © Steve Bulman. 86 NY 708 641. Another view, © Bill Henderson. The Two Churches, so called because it houses both the URC church and serves as St. Wilfred's RC Church. © Bill Henderson. Methodist Church. © Alan Blacklock.
Haydon - see Haydon Bridge, below.
Haydon Bridge.
Heavenfield, St. Oswald. © Bill Henderson. Link.
Hebron, St. Cuthbert. Another view. Both © Lyn Chapple.
Heddon-on-the-Wall, St. Andrew. Link. Methodist Church (formerly Wesleyan). Both © Peter Morgan.
Henshaw, dedicated as All Hallows. 86 NY 764 644. Methodist Church. 86 NY 764 646. Both © Steve Bulman.
Hepple, Christ Church. © Bill McKenzie. Link.
Hexham.
Horsley (Ovingham parish), dedication unknown. © Bill Henderson.
Horsley (in Elsdon parish), Holy Trinity.   Link. © Bill Henderson.
Humshaugh, St. Peter. Another view, and an interior view. NY 920 714. All © John Hall.

Kielder, U.R.C., also used by the Methodist and Anglican congregations. 80 NY 623 941. © Dave Westrap.
Kirknewton, St. Gregory the Great. © Sally Funk.
Knarsdale, St. Jude. © Martin Briscoe. Another view. © Glenn Parker.

Lambley, St. Mary and St. Patrick. Interior view. Both © Alan Blacklock.
Lesbury, St. Mary. 81 NU 236 117. © Steve Bulman. Another view. © Peter Morgan. Link.
Lindisfarne.
Longframlington, St. Mary the Virgin. © Peter Morgan (2009). Link. U.R.C. © Alan Blacklock.
Longhirst, St. John. © Sally Funk.
Longhoughton, St. Peter and St. Paul. © Peter Morgan (2009). Link.
Lowgate, St. Mary. © Alan Blacklock.
Lowick. From the description in Pevsner, I suspect this is St. John. Can you confirm? From an old postcard in Reg Dosell's Collection.

Mitford, St. Mary Magdalene. © Bill Henderson. Link.
Morpeth, St. James the Great. Link. St. Mary the Virgin. Link. U.R.C. All © Bill Henderson.

Newbiggin-by-the-Sea, St. Bartholomew. St. Mark (U.R.C.). St. Mary (R.C.). All  © Bill Henderson. Link.
Newton-by-the-Sea, St. Mary. © Martin Briscoe. Another view, and an interior view, both © Peter Morgan (2009).
Ninebanks. © Steve Bulman. 86 NY 783 525.
North Sunderland, St. Paul (U.R.C.). Interior view. Both © Peter Morgan (2009). Link.

Otterburn, St. John the Evangelist. © Bill McKenzie.
Ovingham, St. Mary. © Peter Morgan. Link.

Ponteland, St. Mary the Virgin. Methodist Church. Both © Bill Henderson.

Rennington, All Saints (1831, additions 1865). © Peter Morgan (2009).
Rothbury.

Seahouses, Methodist Church. © David Gallimore (2009).
Seaton Delaval, Parish Church of Our Lady. From an old postcard, Steve Bulman's Collection. A modern view. © Bill Henderson. Link. Holy Trinity. NZ2975. © Bill Henderson.
Seaton Sluice, St. Paul. © Bill Henderson.
Seghill, Methodist Church. © Bill Henderson.
Shilbottle, St. James. Another view. Both © Peter Morgan (2009). Link.
Simonburn, St. Mungo. Another view, and an interior view. NY 871 736. All © John Hall. Link.
Snods Edge, St. John. © Alan Blacklock. Link.
Stamfordham, St. Mary. The tower. 88 NZ 076 720. Both © Steve Bulman. Link.
Stannington, St. Mary the Virgin. © Bill Henderson.
Stocksfield, Baptist Church. © Alan Blacklock.

Thropton, U.R.C. © Bill McKenzie.

Walbottle, Methodist Church. © Peter Morgan.
Warden, St. Michael and All Angels. The rather attractive lych-gate. John advises that the first church on this site was built in 704 A.D. by Bishop Wilfrid, but the present structure is largely of a re-build of 1764, though there is surviving Saxon work, and some re-used Roman masonry. NY 914 665. Both © John Hall.
Wark (on the North Tyne), St. Michael. NY 857 775. Link. Methodist and U.R.C. NY 860 766. Both © Bill Henderson.
Warkworth, St. Lawrence. © Bill Henderson. Another view. © Steve Bulman. And another. © Alan Craxford. NU 248 063. Interior view, and a tomb, both © Peter Morgan (2009). Link. Remains of the chapel, Warkworth Castle. © Peter Morgan (2009). U.R.C. © Alan Hopkins. Cemetery Chapel (C). Another view. NU 250 063. Both © Steve Bulman (2010). Link.
Whalton, St. Mary Magdalene. © Bill Henderson.
Whitfield, dedicated to Holy Trinity. © Steve Bulman. 86 NY 779 569. St. John. NY 778 584. © Alan Blacklock.
Whittingham, St. Bartholomew. Another view. Interior view. A closer view of the window. All © Steve Bulman. Link.
Widdrington, Holy Trinity. © Alan Craxford. Another view. © Bill Henderson. Link. U.R.C., formerly Widdrington Presbyterian Church. Built in 1893, it replaced an earlier building. NZ 253 955. © Alan Craxford. Another view. Interior view. Both © Lesley Taylor.
Woodhorn, St. Mary the Virgin, now in use as a museum. © Bill Henderson. Link.
Wooler, St. Mary. 75 NT 993 281. © Bill Henderson. An old postcard view, from Reg Dosell's Collection. St. Ninian (R.C.). 75 NT 989 283. © Bill Henderson. U.R.C. 75 NT 993 279. © Steve Bulman.
Wylam, St. Oswin. © Peter Morgan. Link.