A list of worldwide official earthquake surveys that provide (near) real-time earthquake information. Please distinguish between sources with global data (W) and regional data only (R).
Preferred sources for global major earthquake activity
Geoforschunszentrum Potsdam (Germany)
http://geofon.gfz-potsdam.de/eqinfo/seismon/globmon.php
United States Geological Survey (USGS)
https://earthquake.usgs.gov/
European-Mediterranean Seismological Centre (EMSC)
https://www.emsc-csem.org/
Other official sources
Note that some of these sources provide automatic locations that might be poor or errorful.
We cannot guarantee completeness! There are probably many other regional or local earthquake surveys!
Albania: http://www.geo.edu.al/newweb/?fq=bota (R)
Algeria: https://www.craag.dz/ (R)
Argentina: https://www.inpres.gob.ar/desktop/ (R)
Australia: https://earthquakes.ga.gov.au/ (W, R)
Austria: https://www.zamg.ac.at/cms/de/geophysik/erdbeben (W, R)
Azerbaijan: http://www.seismology.az/ (R)
Belarus: http://www.cgm.org.by/index.php?id=384 (W, R)
Belgium: http://seismologie.oma.be/en (R)
Bolivia: http://www.osc.org.bo/index.php/es/ (R)
Bosnia-Herzegowina: http://www.fhmzbih.gov.ba/latinica/index.php (R)
Bosnia-Herzegowina: https://rhmzrs.com/ (R)
Brazil: http://www.moho.iag.usp.br/ (W, R)
Brazil: http://obsis.unb.br/portalsis/ (R)
Canada: http://www.earthquakescanada.nrcan.gc.ca/index-en.php (R)
Chile: http://www.sismologia.cl/ (R)
China: http://news.ceic.ac.cn/index.html (W, R)
Colombia: https://www2.sgc.gov.co/sismos/sismos/ultimos-sismos.html (R)
Costa Rica: http://www.ovsicori.una.ac.cr/index.php/sismos-sentidos (R)
Costa Rica: https://rsn.ucr.ac.cr/actividad-sismica/ultimos-sismos (R)
Czech Republic: https://www.ig.cas.cz/ (R)
Czech Republic: https://sid.ipe.muni.cz/prev.php?lang=cs (R)
Czech Republic, Cheb Basin: https://www.ig.cas.cz/vyzkum-a-vyuka/observatore/lokalni-seismicka-sit-webnet/ (R)
Denmark: https://www.geus.dk/natur-og-klima/jordskaelv-og-seismologi/registrerede-jordskaelv-i-danmark/ (R)
Ecuador: https://www.igepn.edu.ec/ultimos-sismos (R)
Egypt: http://195.43.11.66:9090/earthquakes (R)
El Salvador: http://www.snet.gob.sv/ver/sismologia (R)
Finland: https://www.seismo.helsinki.fi/bulletin/list/alert/current_map.html (R)
France: https://renass.unistra.fr/sismicite/derniers-seismes-en-metropole (R)
France: http://www.franceseisme.fr/ (R)
France: http://www-dase.cea.fr/evenement/derniers_evenements.php?lang=fr (R)
France: http://geoscope.ipgp.fr/index.php/en/ (W)
Georgia: https://ies.iliauni.edu.ge/?page_id=121&lang=ka (R)
Germany: http://geofon.gfz-potsdam.de/eqinfo/seismon/globmon.php (W)
Germany: https://www.szgrf.bgr.de/ (R)
Germany, Bavaria: https://www.erdbeben-in-bayern.de/aktuelle-beben/ (R)
Germany, Hesse: https://www.hlnug.de/themen/geologie/erdbeben/aktuelle-ereignisse (R)
Germany, Lower Saxony: https://www.lbeg.niedersachsen.de/erdbebendienst/erdbebenaktuelles/niedersaechsischer-erdbebendienst-ned-128713.html (R)
Germany, NRW: http://www.seismo.uni-koeln.de/events/index.htm (R)
Germany, NRW: https://www.gd.nrw.de/gg_le_letzten_10_erdbeben.php (R)
Germany, South Western: https://www.lgb-rlp.de/fachthemen-des-amtes/landeserdbebendienst-rheinland-pfalz/erdbebenereignisse-lokal.html (R)
Germany, Ruhr Mining District: https://ariadne.geophysik.ruhr-uni-bochum.de/map/ (R)
Germany, Saxony: http://home.uni-leipzig.de/collm/auswertung_temp.html (R)
Germany, Thuringia: http://www.geophysik.uni-jena.de/Einrichtungen+_+Labore/Th%C3%BCringer+Seismologisches+Netz/Erdbeben.html (R)
Greece: http://geophysics.geo.auth.gr/ (R)
Greece: http://www.gein.noa.gr/el/ (R)
Guatemala: http://insivumeh.gob.gt/geofisica/sismologia/ultimos-sismos-registrados/2019-09-08-0801hrs/ (R)
Hungary: http://www.seismology.hu/index.php/hu (R)
Iceland: https://en.vedur.is/#tab=quakes (R)
India: https://seismo.gov.in/MIS/riseq/earthquake (W, R)
Indonesia: http://inatews.bmkg.go.id/? (R)
Iran: http://irsc.ut.ac.ir/ (R)
Ireland: https://www.insn.ie/confirmed/ (R)
Israel: http://seis.gii.co.il/ (R)
Italy: http://cnt.rm.ingv.it/ (W, R)
Italy: http://www.distav.unige.it/rsni/ (R)
Jamaica: https://www.mona.uwi.edu/earthquake/jaequake.php (R)
Japan: http://www.jma.go.jp/en/quake/quake_local_index.html (R)
Japan: http://www.hinet.bosai.go.jp/ (R)
Japan: http://www.kmoni.bosai.go.jp/ (R)
Kazakhstan: http://www.kndc.kz/index.php?option=com_content&view=article&id=4&Itemid=110&lang=en (R)
Malta: https://seismic.research.um.edu.mt/ (R)
Mexico: http://www.ssn.unam.mx/ (R)
Myanmar: https://www.moezala.gov.mm/earthquake-news%20 (R)
Nepal: http://www.seismonepal.gov.np/ (R)
Netherlands: https://www.knmi.nl/nederland-nu/seismologie/aardbevingen (R)
New Zealand: https://www.geonet.org.nz/ (R)
Nicaragua: https://www.ineter.gob.ni/sismos.html (R)
Norway: http://nnsn.geo.uib.no/nnsn/#/ (R)
Norway: https://www.jordskjelv.no/ (R)
Pakistan: http://seismic.pmd.gov.pk/events.php (W, R)
Peru: http://ultimosismo.igp.gob.pe/ (R)
Philippines: https://www.phivolcs.dost.gov.ph/index.php/earthquake/earthquake-information3 (R)
Portugal: http://www.ipma.pt/pt/geofisica/sismicidade/ (R)
Romania: http://www.infp.ro/ (W, R)
Russia: http://www.ceme.gsras.ru/cgi-bin/ccd_quakee.pl?num=10&x=16&y=1# (W, R)
Russia: http://seis-bykl.ru/ (R)
Serbia: http://www.seismo.gov.rs/ (R)
Singapore: https://www.nea.gov.sg/weather/regional-earthquake-tsunami-alert (R)
Slovakia: http://www.seismology.sk/ (R)
Slowenia: http://potresi.arso.gov.si/zadnji-potresi (R)
South Africa. http://www.geoscience.org.za/index.php/seismic-events1 (R)
South Korea: http://web.kma.go.kr/eng/weather/earthquake/information.jsp (R)
Spain: http://www.ign.es/web/resources/sismologia/tproximos/prox.html (R)
Sweden: http://www.snsn.se/ (R)
Switzerland: http://www.seismo.ethz.ch/de/home/ (W, R)
Taiwan: https://www.cwb.gov.tw/V7/earthquake/ (R)
Thailand: http://www.seismology.tmd.go.th/home.html (R)
Trinidad & Tobago: http://uwiseismic.com/ScientificAdvisories.aspx (R)
Tunisia: http://www.meteo.tn/htmlfr/donnees/seismes2.php (R)
Turkey: http://www.koeri.boun.edu.tr/scripts/lst6.asp (R)
United Arabian Emirates: https://www.ncm.ae/en/index.html#!/Seismology_events/26 (R)
United Kingdom: http://earthquakes.bgs.ac.uk/earthquakes/recent_uk_events.html (W, R)
United States: https://earthquake.usgs.gov/ (W, R)
United States: http://www.iris.edu/seismon/ (W)
United States, Alaska: https://earthquake.alaska.edu/ (R)
United States, California: https://scedc.caltech.edu/recent/Quakes/quakes0.html
United States, Calfornia, Southern: https://www.scsn.org/ (R)
United States, Hawaii: https://volcanoes.usgs.gov/observatories/hvo/hvo_earthquakes.html (R)
United States, Nevada: http://www.seismo.unr.edu/Earthquake (R)
United States, New England States: http://aki.bc.edu/cgi-bin/NESN/recent_events.pl (R)
United States, Oklahoma: http://www.ou.edu/ogs/research/earthquakes/recentearthquakes (R)
United States, Pacific Northwest: https://pnsn.org/ (R)
Uzbekistan: https://rcsm.fvv.uz/ru/catalog_col (R)
Venezuela: http://www.funvisis.gob.ve/index.php (R)
