Booking uses SendGrid as their primary email service provider. They're the #259 most-visited website overall, per Tranco (a web-popularity measure, not an email one). We've also observed sends via SparkPost. Email goes out from 2 different subdomains. Their email authentication setup is solid (score 100/100). We've recorded 1 ESP change since first observing this brand.
Authentication signals observed in this brand's emails. SPF, DKIM and DMARC are the standard sender-authentication stack — see the DMARC policy below for whether spoofing is actually blocked or just monitored. One-click unsubscribe meets Google & Yahoo's bulk-sender requirements.
SPF / DKIM / DMARC above reflect the last 10 emails we've observed. DMARC policy is read live from DNS.
DMARC reports sent to proofpoint.com. Policy
p=reject means receivers actively block or quarantine spoofed mail.
SPF alignment: all 54 observed emails use a return-path aligned with booking.com (sg.booking.com, spe.booking.com, rw.booking.com). SPF authenticates the visible From — supports DMARC directly.
DKIM alignment: all 55 observed emails sign with a domain aligned with booking.com (booking.com, sg.booking.com). DKIM authenticates the visible From — supports DMARC directly.
TLS: 59% TLS 1.3, 41% TLS 1.2 (across 32 sends).
Delivery: fast — 92% of emails in the last 7 days arrive in under 10 seconds (across 12 sends).
Brands often use multiple ESPs (e.g. one for marketing, another for transactional/notifications).
SparkPost 22ESPs we've seen sending email for this brand. Green = confirmed by SPF, sender IP rDNS, or known infra pairing (label shows the source). Grey = observed but not yet confirmed by SPF or PTR.
ESPs this brand has authorized in their SPF record. We confirm them with a green ✓ only after seeing recurring use (3+ emails across 2+ days). Until then they stay here — either we haven't observed any email yet, or we've seen a handful but not enough to call them a regular sender for the brand.
Probed: booking.com, sg.booking.com, spe.booking.com, rw.booking.com
Folder distribution across all emails from this brand observed in Gmail inboxes. High inbox % = good deliverability; spam appearances are the headline signal.
| Folder | Count | Share |
|---|---|---|
| inbox | 47 | 77.0% |
| promotions | 14 | 23.0% |
Which ESP's emails are landing where. Sorted by spam % so problem senders surface first. Brands using one ESP for marketing and another for transactional often see very different placement profiles per ESP. Per-ESP folder data only started being captured recently — counts here may be smaller than the total above until backfill catches up.
| ESP | Emails | Placement | Inbox % | Tabs % | Spam % |
|---|---|---|---|---|---|
| SendGrid | 46 | 78.3% | 21.7% | 0.0% | |
| SparkPost | 15 | 73.3% | 26.7% | 0.0% |
Weekly observations per ESP. Brands often run multiple ESPs concurrently — marketing on one, transactional on another — so this chart shows usage rather than switches.
Bars show tracked opens per week; the line shows what share of those opens included a real click somewhere in the email. Click tracking just started (July 2026, Gmail only) — expect this to fill in gradually rather than show much history yet.
IP addresses booking.com has been observed sending from, and where their mail landed in Gmail.
| IP | Hostname | Obs | Placement | Reputation |
|---|---|---|---|---|
| 192.174.95.219 | mta-174-95-219.booking.com.sparkpostmail.com |
10 | 6 | Check → |
| 149.72.129.233 | o31.sg.booking.com |
7 | — | Check → |
| 167.89.6.174 | o12.sg.booking.com |
6 | — | Check → |
| 208.117.50.32 | o1.sg.booking.com |
5 | 3 | Check → |
| 167.89.88.98 | o21.sg.booking.com |
3 | — | Check → |
| 167.89.15.14 | o14.sg.booking.com |
3 | — | Check → |
| 192.254.126.45 | o7.sg.booking.com |
3 | — | Check → |
| 167.89.96.8 | o19.sg.booking.com |
3 | — | Check → |
| 198.21.4.145 | o9.sg.booking.com |
3 | 3 | Check → |
| 192.254.126.47 | o8.sg.booking.com |
2 | — | Check → |
| 192.174.95.216 | mta-174-95-216.booking.com.sparkpostmail.com |
2 | — | Check → |
| 167.89.48.168 | o17.sg.booking.com |
2 | — | Check → |
| 50.31.33.210 | o5.sg.booking.com |
2 | — | Check → |
| 167.89.15.148 | o15.sg.booking.com |
2 | — | Check → |
| 50.31.33.211 | o6.sg.booking.com |
2 | — | Check → |
| 192.174.95.230 | mta-174-95-230.booking.com.sparkpostmail.com |
2 | 1 | Check → |
| 167.89.15.150 | o16.sg.booking.com |
1 | — | Check → |
| 192.254.122.159 | o18.sg.booking.com |
1 | — | Check → |
| 192.174.95.231 | mta-174-95-231.booking.com.sparkpostmail.com |
1 | — | Check → |
| 192.174.95.227 | mta-174-95-227.booking.com.sparkpostmail.com |
1 | — | Check → |
| 192.174.95.225 | mta-174-95-225.booking.com.sparkpostmail.com |
1 | — | Check → |
| 167.89.96.75 | o20.sg.booking.com |
1 | — | Check → |
| 192.174.95.232 | mta-174-95-232.booking.com.sparkpostmail.com |
1 | — | Check → |
| 167.89.6.175 | o13.sg.booking.com |
1 | — | Check → |
| 149.72.129.23 | o27.sg.booking.com |
1 | — | Check → |