Funny, I just posted this to my German forum ;-) Here is the current list from the tourist office in Old Town:
Laboratorio Clínico COMPOSTELA
Rúa Xeneral Pardiñas 10 - 12, Semisótano 8 (2C on the map)
15701 Santiago de Compostela
Tel: +34 981 562 462
Monday to Friday, 8:30h to 13:00 h and from 17:00 to 19:00 h / Saturday: with an appointment
info@laboratorioclinicocompostela.es
http://www.laboratorioclinicocompostela.es/#Contacto
LABORATORIO J. DE SOTO
Dr. Teixeiro, 19 (3C on the map)
Santiago de Compostela, A Coruña
Tel: +34 981 566 332
Monday to Friday, from 8:00 to 14:00 and from 17:00 to 19:00
https://www.laboratoriojacobodesoto.com/
LIFECLINIC
República do Salvador, 23 – 1ºA (2C on the map)
Santiago de Compostela, A Coruña
Tel: +34 881 293 441 / +34 722 707 063
Opening from 10:00 to 18:00
info@lifeclinic.es
https://lifeclinic.es/.../pcr-con-toma-de-muestra-por.../
HOSPITAL HM ROSALEDA
Rúa de Santiago León de Caracas, 1 (3B on the map)
15701 Santiago de Compostela, A Coruña
Telf. +34 981 551 200
https://www.hmhospitales.com/.../pruebas-deteccion-covid
QUIRÓN PREVENCIÓN
Av. Liberdade, 11 (1A on the map )
15706 Santiago de Compostela, A Coruña
Telf. +34 981 534 470
Monday to Friday, from 7:30 to 15:00 h
https://e-quironsalud.es/26-test-covid Tel. +34 91 122 14 52
https://www.quironprevencion.com/es/pruebas-covid-19
CLÍNICA GAIAS
Rúa do Pintor Xaime Quesada, 2, 4 (3B on the map)
+34 981 56 68 01 /
https://clinicagaias.com
PCR: Monday to Thursday from 12:00 – 12:15h / 48h before the flight
Antigen test: Monday to Friday from 12-13:30
Revimedic
Rúa de Santo Domingo de la Calzada, 6, 2ºC (2C on the map)
Tel: +34 981 59 52 23
SUEVIA SERVICIOS GENERALES (antigen COVID test on Saturday and Sunday with an appointment)
Rúa Magdalena, 11- bajo 6.
15895 Milladoiro (Ames) A Coruña (6 Km away from Santiago)
From 9 am to 8 pm
Telfs. +34 881 087 551 / +34 676 470 775 / +34 628 221 719
info@suevia.gal
https://www.sueviasalud.es