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Postmark

Transactional Email Service

Fast transactional email delivery.

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257 brands detected that use Postmark (195 as primary ESP)

Postmark is the 5th most popular transactional ESP we track.

Detected by 259 distinct extension users.

Industries using Postmark

Distribution of brands using Postmark by industry. Helps you gauge whether this ESP is popular with businesses similar to yours. Brands tagged in two industries are counted in both.

SaaS 87 brands · 39.2% Marketing & Agencies 54 brands · 24.3% Education 13 brands · 5.9% Media 12 brands · 5.4% E-commerce 10 brands · 4.5% Professional Services 10 brands · 4.5% Finance 6 brands · 2.7% Entertainment 5 brands · 2.3% Health 4 brands · 1.8% Retail 4 brands · 1.8% Food & Beverage 4 brands · 1.8% Other 3 brands · 1.4% Real Estate 3 brands · 1.4% Travel 3 brands · 1.4% Nonprofit 2 brands · 0.9% Manufacturing 1 brand · 0.5% Telecom 1 brand · 0.5%

Based on 222 of 257 brands tagged (86% coverage). Industries assigned automatically using AI; not every brand is tagged yet.

Average placement for brands using Postmark

Where this ESP's emails land in Gmail. Each brand counted once (average of per-brand percentages) so a single high-volume sender can't dominate. Spam placement is mostly driven by the sender (list quality, content, complaint rate). This number reflects both the ESP's infrastructure AND the kind of senders who choose it — not just deliverability quality.

inbox 95.6%promotions 4.1%spam 0.3%

By volume: inbox 3,297 · promotions 166 · spam 19 (3,482 emails observed)

Percentages are averaged per brand (each counted once) across 100 brands using Postmark with at least 5 placement observations each.

257 brands use Postmark

195 as their primary ESP, the rest send transactional or secondary email through it. Primary users are listed first, then secondary.

Sort: Importance | Most spam
Compare Postmark with:
Brand Role Obs Spam Last seen
Withgoogle
withgoogle.com
primary 2 2026-06-10
Livechatinc
livechatinc.com
primary 5 0.0% 2026-06-28
Gamma
gamma.app
primary 6 0.0% 2026-06-17
Judge
judge.me
primary 11 0.0% 2026-06-26
Buymeacoffee
buymeacoffee.com
primary 2 2026-06-02
Livechat
livechat.com
primary 2 2026-06-18
16personalities
16personalities.com
primary 2 0.0% 2026-06-26
Kustomerapp
kustomerapp.com
primary 1 2026-05-26
Supabase
supabase.com
primary 14 0.0% 2026-06-30
Thenounproject
thenounproject.com
primary 1 2026-05-25
Hover
hover.to
primary 3 0.0% 2026-06-03
Letyshops
letyshops.com
primary 3 0.0% 2026-05-13
Paddle
paddle.com
primary 25 0.0% 2026-06-28
Cal
cal.com
primary 16 0.0% 2026-06-29
99designs
99designs.com
primary 15 0.0% 2026-05-28
Profitwell
profitwell.com
primary 14 0.0% 2026-06-29
Builtwith
builtwith.com
primary 2 2026-06-21
Render
render.com
primary 1 2026-05-02
Docsend
docsend.com
primary 1 2026-05-02
Toogoodtogo
toogoodtogo.com
primary 17 0.0% 2026-06-24
Waveapps
waveapps.com
primary 3 0.0% 2026-06-22
Digistore24
digistore24.com
primary 3 0.0% 2026-06-08
Fathom
fathom.video
primary 78 0.0% 2026-06-26
Gleap
gleap.io
primary 1 2026-06-03
Postmarkapp
postmarkapp.com
primary 83 0.0% 2026-06-22
Applytojob
applytojob.com
primary 3 0.0% 2026-06-11
Planespotters
planespotters.net
primary 1 2026-05-25
Workos
workos.com
primary 8 0.0% 2026-05-06
Fillout
fillout.com
primary 4 0.0% 2026-06-26
Bigmarker
bigmarker.com
primary 5 0.0% 2026-06-16
Bitpanda
bitpanda.com
primary 2 2026-06-18
Balsamiq
balsamiq.com
primary 2 2026-06-28
Firstpromoter
firstpromoter.com
primary 55 0.0% 2026-06-29
Thrivethemes
thrivethemes.com
primary 15 0.0% 2026-06-08
Uscreen
uscreen.io
primary 2 2026-06-09
Goldcast
goldcast.io
primary 17 0.0% 2026-06-25
K Rauta
k-rauta.ee
primary 7 0.0% 2026-06-15
Drata
drata.com
primary 1 2026-06-04
Arbitersports
arbitersports.com
primary 3 0.0% 2026-06-26
Mealtrain
mealtrain.com
primary 2 2025-09-05
Userjot
userjot.com
primary 1 2026-06-17
Bookfunnel
bookfunnel.com
primary 1 2026-06-12
Blinq
blinq.me
primary 1 2026-05-04
Lattice
lattice.com
primary 5 0.0% 2026-05-21
Clearcompany
clearcompany.com
primary 1 2026-05-22
Pinpointhq
pinpointhq.com
primary 3 0.0% 2026-06-22
My Hammer
my-hammer.de
primary 1 2026-06-04
Santalolla
santalolla.com.br
primary 3 100% 2026-05-04
Metorik
metorik.com
primary 1 2026-05-01
Ia
ia.net
primary 1 2026-05-02
Smartlead
smartlead.ai
primary 5 0.0% 2026-06-14
Buttondown
buttondown.email
primary 2 2026-06-24
Fountain
fountain.fm
primary 2 2026-05-22
Castr
castr.com
primary 1 2026-06-26
Saleshandy
saleshandy.com
primary 8 0.0% 2026-06-29
Helpdesk
helpdesk.com
primary 6 0.0% 2026-06-26
Proton
proton.ch
primary 1 2026-04-08
Amplemarket
amplemarket.com
primary 1 2026-05-11
Spar
spar.co.za
primary 1 2026-06-22
Benchapp
benchapp.com
primary 7 0.0% 2026-06-08
Happyreturns
happyreturns.com
primary 1 2026-05-07
Remotive
remotive.com
primary 1 2026-06-29
Qualia
qualia.com
primary 4 0.0% 2026-05-19
Joinboulevard
joinboulevard.com
primary 1 2026-06-11
Langdock
langdock.com
primary 1 2026-05-21
Dataforseo
dataforseo.com
primary 3 0.0% 2026-06-23
Zenmaid
zenmaid.com
primary 3 0.0% 2026-06-20
Pentest Tools
pentest-tools.com
primary 2 2026-05-13
Heartbeat
heartbeat.chat
primary 11 0.0% 2026-06-29
Spotdraft
spotdraft.com
primary 1 2026-06-17
Thingtesting
thingtesting.com
primary 1 2026-05-24
Malcare
malcare.com
primary 5 0.0% 2026-06-18
Property
property.ca
primary 2 2026-06-01
Tideways
tideways.com
primary 1 2026-05-06
Heartbingo
heartbingo.co.uk
primary 1 2026-05-21
Schedulista
schedulista.com
primary 1 2026-05-21
Blvd
blvd.co
primary 11 0.0% 2026-06-10
Savvycal
savvycal.com
primary 27 0.0% 2026-06-27
Unleash
unleash.ai
primary 1 2026-05-16
Fireship
fireship.dev
primary 1 2026-06-20
Memberspot
memberspot.de
primary 4 0.0% 2026-06-25
Woorise
woorise.com
primary 2 2026-06-11
Drawnames
drawnames.com
primary 1 2026-05-27
Rewardful
rewardful.com
primary 33 0.0% 2026-06-21
Primelending
primelending.com
primary 5 0.0% 2026-06-24
Lacompagnie
lacompagnie.com
primary 1 2026-05-23
Torre
torre.ai
primary 1 2026-06-08
Mentorcruise
mentorcruise.com
primary 2 0.0% 2026-06-29
Parnassys
parnassys.net
primary 3 0.0% 2026-06-23
Tinyemail
tinyemail.com
primary 2 0.0% 2026-06-17
Fsenrollment
fsenrollment.com
primary 3 0.0% 2026-06-26
Shopaew
shopaew.com
primary 1 2026-05-31
Salesforge
salesforge.ai
primary 1 2026-05-22
Kritische Anleger
kritische-anleger.de
primary 1 2026-04-28
Clarel
clarel.es
primary 2 2026-06-01
Conveyor
conveyor.com
primary 3 0.0% 2026-06-16
Famewall
famewall.io
primary 1 2026-06-03
Woojer
woojer.com
primary 1 2024-11-26
Servicespace
servicespace.org
primary 2 2026-06-11
Rarebookcellar
rarebookcellar.com
primary 1 2026-06-08
Showing the top 100 of 257 brands by observations · Show all

Sending IPs (top 25)

IPs we've observed sending via Postmark. "Brands" = distinct brands seen on each IP; "Placement" = where those emails landed in Gmail (inbox / promotions / spam). Click "reputation" to check the IP on Cisco Talos.

IPHostnameBrandsObsPlacementReputation
50.31.156.116 sc-ord-mta116.mtasv.net 22 81 6 Check →
50.31.156.115 sc-ord-mta115.mtasv.net 20 80 7 Check →
50.31.156.126 sc-ord-mta126.mtasv.net 23 75 9 Check →
50.31.156.120 sc-ord-mta120.mtasv.net 18 72 12 Check →
50.31.156.113 sc-ord-mta113.mtasv.net 13 65 9 Check →
50.31.156.118 sc-ord-mta118.mtasv.net 22 62 7 Check →
50.31.156.117 sc-ord-mta117.mtasv.net 21 60 14 Check →
50.31.156.121 sc-ord-mta121.mtasv.net 21 55 11 Check →
50.31.156.114 sc-ord-mta114.mtasv.net 19 52 6 Check →
50.31.156.124 sc-ord-mta124.mtasv.net 16 44 9 Check →
104.245.209.196 mta196a-ord.mtasv.net 19 35 6 Check →
104.245.209.198 mta198a-ord.mtasv.net 16 35 9 Check →
104.245.209.210 mta210a-ord.mtasv.net 19 34 2 Check →
104.245.209.203 mta203a-ord.mtasv.net 12 31 3 Check →
104.245.209.215 mta215a-ord.mtasv.net 14 31 3 Check →
104.245.209.212 mta212a-ord.mtasv.net 13 30 6 Check →
104.245.209.213 mta213a-ord.mtasv.net 13 29 6 Check →
104.245.209.197 mta197a-ord.mtasv.net 18 28 8 Check →
50.31.205.203 mta203-ab1.mtasv.net 11 27 2 Check →
50.31.205.220 mta220-ab1.mtasv.net 15 26 5 Check →
104.245.209.235 mta235b-ord.mtasv.net 11 25 5 Check →
104.245.209.202 mta202a-ord.mtasv.net 14 25 3 Check →
104.245.209.200 mta200a-ord.mtasv.net 9 22 6 Check →
104.245.209.199 mta199a-ord.mtasv.net 14 22 3 Check →
50.31.205.204 mta204-ab1.mtasv.net 9 21 Check →