Inbox placement of the .co Google mailboxes

GlockApps Inbox Insight tests, 3 November 2026. One mailbox per domain, 7 business seed mailboxes per test (5 Google Workspace, 2 Microsoft 365). Everything that did not reach the inbox landed in spam; nothing was missing.

DomainMailboxInboxGoogle Workspace (4+ years)Google Workspace (up to 6 months)Microsoft 365SPF / DKIM / DMARC
Domain 2mailbox on Domain 23/70/31/22/2pass / pass / pass
Domain 4mailbox on Domain 41/70/31/20/2pass / pass / pass
Domain 1mailbox on Domain 11/70/30/21/2pass / pass / pass
Domain 3mailbox on Domain 31/70/31/20/2pass / pass / pass
Domain 5mailbox on Domain 53/70/31/22/2pass / pass / pass
Domain 6mailbox on Domain 61/70/30/21/2pass / pass / pass
Domain 7mailbox on Domain 70/70/30/20/2pass / pass / pass
Domain 8mailbox on Domain 81/70/30/21/2pass / pass / pass
All 8 domains11/560/244/167/16

For comparison, the same message sent directly from Gmail on our main Google Workspace domain on 2 November: 7/7 inbox.

SURBL status of all 8 .co domains

Live DNS lookup of <domain>.multi.surbl.org, 3 November 2026. A 127.0.0.64 answer means the domain is on the SURBL ABUSE list. The lookup output is kept on file.

DomainSURBL
Domain 1not listed
Domain 2listed (127.0.0.64, ABUSE)
Domain 3not listed
Domain 4listed (127.0.0.64, ABUSE)
Domain 5not listed
Domain 6not listed
Domain 7not listed
Domain 8listed (127.0.0.64, ABUSE)

How the tests were run

Domain 2

Test 2026-11-03-08:45:47:828t, created 2026-11-03 08:45:47 UTC. Sender: one mailbox on Domain 2, 8 of 8 seed messages sent between 08:47:43 and 09:07:14 UTC, 0 bounces. Sending IP 209.85.216.44 (mail-pj1-f44.google.com). GlockApps flags: GAPPS_BOOK_A_CALL, SENDER_DOMAIN_IN_BLOCKLIST, GAPPS_WARM_UP.

Seed groupSeedPlacement
Google Workspace (up to 6 months)seed 1Spam
Google Workspace (up to 6 months)seed 2Inbox
Microsoft 365seed 3Inbox
Google Workspace (4+ years)seed 4Spam
Google Workspace (4+ years)seed 5Spam
Microsoft 365seed 6Inbox
Google Workspace (4+ years)seed 7Spam

Domain 4

Test 2026-11-03-08:48:09:659t, created 2026-11-03 08:48:09 UTC. Sender: one mailbox on Domain 4, 8 of 8 seed messages sent between 08:49:42 and 09:09:35 UTC, 0 bounces. Sending IP 209.85.216.48 (mail-pj1-f48.google.com). GlockApps flags: GAPPS_BOOK_A_CALL, SENDER_DOMAIN_IN_BLOCKLIST, GAPPS_WARM_UP.

Seed groupSeedPlacement
Google Workspace (4+ years)seed 1Spam
Google Workspace (4+ years)seed 2Spam
Microsoft 365seed 3Spam
Google Workspace (4+ years)seed 4Spam
Google Workspace (up to 6 months)seed 5Spam
Google Workspace (up to 6 months)seed 6Inbox
Microsoft 365seed 7Spam

Domain 1

Test 2026-11-03-08:48:17:447t, created 2026-11-03 08:48:17 UTC. Sender: one mailbox on Domain 1, 8 of 8 seed messages sent between 08:49:40 and 09:09:35 UTC, 0 bounces. Sending IP 209.85.210.178 (mail-pf1-f178.google.com). GlockApps flags: GAPPS_BOOK_A_CALL, GAPPS_WARM_UP.

Seed groupSeedPlacement
Microsoft 365seed 1Spam
Google Workspace (4+ years)seed 2Spam
Google Workspace (4+ years)seed 3Spam
Microsoft 365seed 4Inbox
Google Workspace (4+ years)seed 5Spam
Google Workspace (up to 6 months)seed 6Spam
Google Workspace (up to 6 months)seed 7Spam

Domain 3

Test 2026-11-03-09:28:41:079t, created 2026-11-03 09:28:41 UTC. Sender: one mailbox on Domain 3, 8 of 8 seed messages sent between 09:31:46 and 09:51:31 UTC, 0 bounces. Sending IP 209.85.214.179 (mail-pl1-f179.google.com). GlockApps flags: GAPPS_BOOK_A_CALL, GAPPS_WARM_UP.

Seed groupSeedPlacement
Google Workspace (4+ years)seed 1Spam
Google Workspace (4+ years)seed 2Spam
Microsoft 365seed 3Spam
Google Workspace (4+ years)seed 4Spam
Google Workspace (up to 6 months)seed 5Spam
Google Workspace (up to 6 months)seed 6Inbox
Microsoft 365seed 7Spam

Domain 5

Test 2026-11-03-09:28:49:097t, created 2026-11-03 09:28:49 UTC. Sender: one mailbox on Domain 5, 8 of 8 seed messages sent between 09:32:55 and 09:51:51 UTC, 0 bounces. Sending IP 209.85.210.171 (mail-pf1-f171.google.com). GlockApps flags: GAPPS_BOOK_A_CALL, GAPPS_WARM_UP.

Seed groupSeedPlacement
Google Workspace (up to 6 months)seed 1Inbox
Microsoft 365seed 2Inbox
Google Workspace (4+ years)seed 3Spam
Google Workspace (4+ years)seed 4Spam
Microsoft 365seed 5Inbox
Google Workspace (4+ years)seed 6Spam
Google Workspace (up to 6 months)seed 7Spam

Domain 6

Test 2026-11-03-09:29:51:599t, created 2026-11-03 09:29:51 UTC. Sender: one mailbox on Domain 6, 8 of 8 seed messages sent between 09:31:57 and 09:51:45 UTC, 0 bounces. Sending IP 209.85.210.181 (mail-pf1-f181.google.com). GlockApps flags: GAPPS_BOOK_A_CALL, GAPPS_WARM_UP.

Seed groupSeedPlacement
Google Workspace (4+ years)seed 1Spam
Microsoft 365seed 2Inbox
Google Workspace (4+ years)seed 3Spam
Google Workspace (up to 6 months)seed 4Spam
Google Workspace (up to 6 months)seed 5Spam
Microsoft 365seed 6Spam
Google Workspace (4+ years)seed 7Spam

Domain 7

Test 2026-11-03-09:30:00:979t, created 2026-11-03 09:30:00 UTC. Sender: one mailbox on Domain 7, 8 of 8 seed messages sent between 09:31:48 and 09:51:44 UTC, 0 bounces. Sending IP 209.85.216.46 (mail-pj1-f46.google.com). GlockApps flags: GAPPS_BOOK_A_CALL, GAPPS_WARM_UP.

Seed groupSeedPlacement
Microsoft 365seed 1Spam
Google Workspace (4+ years)seed 2Spam
Google Workspace (4+ years)seed 3Spam
Microsoft 365seed 4Spam
Google Workspace (4+ years)seed 5Spam
Google Workspace (up to 6 months)seed 6Spam
Google Workspace (up to 6 months)seed 7Spam

Domain 8

Test 2026-11-03-09:30:08:433t, created 2026-11-03 09:30:08 UTC. Sender: one mailbox on Domain 8, 8 of 8 seed messages sent between 09:31:54 and 09:51:43 UTC, 0 bounces. Sending IP 209.85.214.173 (mail-pl1-f173.google.com). GlockApps flags: GAPPS_BOOK_A_CALL, SENDER_DOMAIN_IN_BLOCKLIST, GAPPS_WARM_UP.

Seed groupSeedPlacement
Google Workspace (4+ years)seed 1Spam
Google Workspace (up to 6 months)seed 2Spam
Google Workspace (up to 6 months)seed 3Spam
Microsoft 365seed 4Spam
Google Workspace (4+ years)seed 5Spam
Google Workspace (4+ years)seed 6Spam
Microsoft 365seed 7Inbox

Raw GlockApps results: results.json.