More than 1,000 fax machines are still in use at hospitals and GP surgeries across Wales - technology dubbed "a relic" by one of Wales' top doctors.
There are at least 1,063 in the seven Welsh NHS health boards and £550,000 has been spent on supplies since 2015.
Betsi Cadwaladr - the largest health board - has between 450 and 500. By comparison, Aneurin Bevan has 17.
The Welsh Government said it expected the use of fax machines to "continue to decline" as technology progressed.
Abertawe Bro Morgannwg has bought 176 fax machines since 2015, but did not specify its total.
There are still about 260 in Cwm Taf and 34 in Powys. Hywel Dda said an audit in 2016-17 showed it had 76.
In reality, the figure is much higher because Cardiff and Vale does not store the data, while Abertawe Bro Morgannwg in the Swansea area acknowledged there were "100s of historic fax machines being utilised".
Betsi Cadwaladr in north Wales said it was phasing out fax machines and had seen "a significant reduction in spending on fax machines and supplies in the past three years going from £28,251 in 2015 to £391 this year".
Dr David Bailey, the British Medical Association Welsh Council chairman, said fax machines did nothing that was not quicker and easier via secure email - which the NHS already uses.
"For all sorts of reasons it is a relic - you probably need a little while to get rid of them all," added Dr Bailey, who runs a GP practice in Caerphilly
"I expect the younger generation of doctors would be astonished to see a fax machine."
Despite Betsi having the most machines, it has spent £32,690 on supplies since 2015-16, compared with £31,978.87 by Cardiff and Vale and £43,040.66 by Abertawe Bro Morgannwg.
Powys spent £8,925.99, Aneurin Bevan in Gwent £18,232.06, Hywel Dda in west Wales £76,458.92 but the expenditure of Cwm Taf in the Valleys was £340,381.19.
Cwm Taf said it was moving from stand-alone machines to "more cost effective" devices that copy, print and scan.
It said its high spend was because the cost included materials for printers so "cannot be directly compared with fax only expenditure".
Health is devolved to the Welsh Government, but the NHS in England can no longer buy fax machines as of January.
The Welsh Government has not followed this directive, but said it was "committed to increasing access to information through digital services and therefore expect the use of faxes to continue to decline".
Fax for the memories
- Scotsman Alexander Bain invented the first experimental fax machine in 1842
- It scanned a message written with special ink on a metallic surface. This picked up the electrical impression of the original and a telegraph circuit was used to transmit it
- Organisations adopted the technology in the 20th Century
- After technological improvements by Japanese companies, they became widespread in the 1970s and 1980s
- The technology peaked towards the end of the 20th Century