Fastmail

fastmail.com

Fastmail declares 35 subprocessors, plus 1 of its own affiliates, in its subprocessor list, which we last checked on Nov 11, 2026 (evidence). They include Microsoft, Stripe and Anthropic. No published changes since we first read it on Sep 21, 2026. 6 tracked vendors name Fastmail as a subprocessor, including Fathom Analytics, Sendmarc and Hund.

Subprocessors CSV · Atom DORA draft CSV what's this? · 

35 third parties, 1 affiliate.

NamePurposeLocationListed since
Abusix Antispam/antifraud/antiabuse management
Anthropic PBC AIBusiness operations and support services
Avalara AvaTax Business operations
CentralNic Reseller (RRPproxy) Domain registration and management
Cloudflare Content distribution, security, abuse prevention and DNS services
DeepL Translation services, primarily for support tickets and non-English spam and phishing content review
DNSWL Antispam/antifraud/antiabuse management
DropBox Support services and Business operations
eFax (j2connect) Support services and Business operations
eHawk Antispam/antifraud/antiabuse management
GitHub Hosting of code as an open source tool
Grammarly Writing assistance, primarily for support tickets
hCaptcha Antispam/antifraud/antiabuse management
Linear Project management and Business operations
Mailchimp Email marketing and automation
Microsoft Cloud-based and on-premises office productivity tools
Notion Support services and Business operations
Paddle Payment processing
PagerDuty Support services and Incident management
Partnerstack Partner and referral management
Paypal Payment processing
Pin Payment processing
Posthog Analytics in order to improve user experience.
Pythia Support services
Redsift Antispam/antifraud/antiabuse management
Sentry Application logging
Slack Support services and Business operations
Spamhaus Antispam/antifraud/antiabuse management
Stripe Payment processing
SurveyMonkey Support services, Customer feedback and Business operations
Twilio Multi-factor authentication
Vade (Hornet Security) Antispam/antifraud/antiabuse management
Validity Antispam/antifraud/antiabuse management
Zendesk Support services
Zoom Video conferencing
Fastmail affiliates (1)
NamePurposeLocationListed since
Fastmail US LLC Business operations

Web TechnologiesCSV · Atom

Fastmail's homepage made 41 requests to 1 domain.

First party 1 · 41 requests
Fastmail Cloudflare HSTS HTTP/3 Open Graph PWA 100% of the page's requests 41

Subprocessor of (6)CSV · Atom

6 companies

Service statusCSV · Atom

Aug 15: no incident reportedAug 16: no incident reportedAug 17: no incident reportedAug 18: no incident reportedAug 19: no incident reportedAug 20: no incident reportedAug 21: no incident reportedAug 22: no incident reportedAug 23: no incident reportedAug 24: no incident reportedAug 25: 1 incident (1 no impact stated)Aug 26: no incident reportedAug 27: no incident reportedAug 28: no incident reportedAug 29: no incident reportedAug 30: no incident reportedAug 31: no incident reportedSep 1: no incident reportedSep 2: no incident reportedSep 3: no incident reportedSep 4: 1 incident (1 no impact stated)Sep 5: no incident reportedSep 6: no incident reportedSep 7: no incident reportedSep 8: no incident reportedSep 9: no incident reportedSep 10: no incident reportedSep 11: no incident reportedSep 12: no incident reportedSep 13: no incident reportedSep 14: no incident reportedSep 15: no incident reportedSep 16: no incident reportedSep 17: no incident reportedSep 18: no incident reportedSep 19: no incident reportedSep 20: no incident reportedSep 21: no incident reportedSep 22: no incident reportedSep 23: 1 incident (1 no impact stated)Sep 24: no incident reportedSep 25: no incident reportedSep 26: no incident reportedSep 27: no incident reportedSep 28: no incident reportedSep 29: no incident reportedSep 30: no incident reportedOct 1: no incident reportedOct 2: no incident reportedOct 3: no incident reportedOct 4: no incident reportedOct 5: 1 incident (1 no impact stated)Oct 6: no incident reportedOct 7: 1 incident (1 no impact stated)Oct 8: no incident reportedOct 9: no incident reportedOct 10: no incident reportedOct 11: no incident reportedOct 12: no incident reportedOct 13: no incident reportedOct 14: 1 incident (1 no impact stated)Oct 15: no incident reportedOct 16: no incident reportedOct 17: no incident reportedOct 18: no incident reportedOct 19: no incident reportedOct 20: no incident reportedOct 21: no incident reportedOct 22: no incident reportedOct 23: no incident reportedOct 24: no incident reportedOct 25: no incident reportedOct 26: no incident reportedOct 27: no incident reportedOct 28: no incident reportedOct 29: 1 incident (1 no impact stated)Oct 30: no incident reportedOct 31: no incident reportedNov 1: no incident reportedNov 2: no incident reportedNov 3: no incident reportedNov 4: no incident reportedNov 5: no incident reportedNov 6: no incident reportedNov 7: no incident reportedNov 8: no incident reportedNov 9: no incident reportedNov 10: no incident reportedNov 11: no incident reportedNov 12: no incident reported

90 days agotoday

  • 7 incidents in 90 days
  • 0 major or critical
  • 5 h 23 min typical time to resolve
BeganIncidentImpactLasted
Support emails not generating ticketsno impact stated1 h 20 min
Support web form not accessibleno impact stated9 min
Interrupted access to Fastmail servicesno impact stated5 h 23 min
Support emails not generating ticketsno impact stated2 days
Replies sent using masked email addresses are bouncingno impact stated11 h 12 min
Interrupted access to Fastmail servicesno impact stated1 h 8 min
Interrupted access to Fastmail servicesno impact stated8 h 16 min
Interrupted access to Fastmail servicesno impact stated1 h 53 min

Incidents per month

0 3 6 Dec 2025: 1 incident (1 no impact stated) · typical time to resolve 1 h 15 min Jan 2026: 5 incidents (5 no impact stated) · typical time to resolve 1 h 44 min Feb 2026: 1 incident (1 no impact stated) · typical time to resolve 2 min Mar 2026: 1 incident (1 no impact stated) · typical time to resolve 2 h 19 min Apr 2026: 0 incidents May 2026: 4 incidents (4 no impact stated) · typical time to resolve 1 h 54 min Jun 2026: 0 incidents Jul 2026: 0 incidents Aug 2026: 1 incident (1 no impact stated) · typical time to resolve 8 h 16 min Sep 2026: 2 incidents (2 no impact stated) · typical time to resolve 11 h 12 min Oct 2026: 4 incidents (4 no impact stated) · typical time to resolve 5 h 23 min Nov 2026: 0 incidents Dec 2025Jan 2026Feb Mar Apr May Jun Jul Aug Sep Oct Nov

critical major minor no impact stated

Components affected

ComponentIncidents
Support Tickets3
Calendar (CalDAV)1
Contacts (CardDAV)1
File storage (WebDAV)1
General Availability1
Login & sessions1
Mail access (IMAP/POP)1
Mail delivery1

As Fastmail's status page reports its own incidents (scheduled maintenance left out), read every few hours since (evidence)

Incidents reported by Fastmail's subprocessorsCSV · Atom

300 reported incidents in the last 30 days, by 13 of the vendors Fastmail lists as subprocessors.

A subprocessor list names a company, not the service an incident touched. This does not show that Fastmail was involved.

DateCompanyIncidentImpactLasted
TwilioMMS Delivery Failures from Twilio to GCI United States minor3 min
TwilioSMS Delivery Failures from Twilio 10DLC to AT&T United States minor4 h 3 min
TwilioSMS Delivery Failures from Twilio to Orange Sierra Leone minorongoing
TwilioSMS Delivery Failures From Long Code Numbers to AT&T in the US minor1 h 19 min
TwilioSMS Delivery Delays from Twilio to MTS Kazakhstan minorongoing
TwilioSMS Delivery Failures from a Subset of Twilio Phone Numbers to Tcell Tajikistan minorongoing
TwilioMMS Delivery Delays from a Subset of Twilio Long Codes to Multiple Small Networks in United States minorongoing
TwilioSMS Delivery Failures from a Subset of Twilio Phone Numbers to K-Cell Kazakhstan minor7 h 23 min
GitHubImpact across multiple GitHub products including Actions, Pages, and Copilot products. critical33 min
GitHubIncident with Webhooks minor4 min
SentryUS issues feed throwing intermittent errors minor51 min
TwilioVoice Call Failures in JP1 minor3 h 51 min
SurveyMonkeyPROD-TEST - THIS IS A TEST - PLEASE IGNORE, no impact stated1 min
LinearSlack integration degraded due to Slack outage minor3 h 9 min
TwilioSMS Delivery Failures from Twilio to Turkcell Turkey minor3 h 54 min
SentryAccount emails not being delivered major42 min
TwilioRetroactive Incident Impacting Twilio Usage APIs no impact stated1 min
AnthropicElevated errors on Fable 52 and Mythos 52 no impact stated1 min
TwilioIssue resolved minor1 h 43 min
SentryEU region replay ingestion latency minor48 min
ZoomService Degradation Affecting Zoom Conference Room Connector Services Endpoints in the AMS region. minor2 h 35 min
SurveyMonkeyTEST INCIDENT #2 major4 min
NotionSome Notion Agent sessions may hang or stop updating major2 h 19 min
SurveyMonkeyTEST INCIDENT #1 no impact stated22 min
TwilioSMS Delivery Receipt Delays from Twilio Phone Numbers to Movistar Venezuela minor3 h 26 min

And 275 more. All of them: CSV · Who is around them.

ChangesCSV · Atom

See the list as we read it on any date: Time machine

None since tracking began.

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Fastmail transparency rating

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