sendgrid IP blocked

There are two distinct situations both described as "SendGrid IP blocked," and the fix is completely different for each. Identify which one you have before acting.

1. Your sending IP is on a blocklist (deny list). Receiving inbox providers reject your mail because the IP that sent it is listed for spam/abuse. This shows up as blocked messages in your account.
2. IP Access Management blocked your own access. SendGrid's IP Access Management feature restricts UI/API/SMTP login to an allowlist of IPs — if your current IP isn't on it, you're locked out of the account (not a deliverability problem).

What causes "SendGrid IP blocked"?

For blocked messages, SendGrid lists three causes: someone added your mail server IP to a blocklist, an ISP blocked your mail server IP, or a filter on the receiving server flagged your message content. The exact reason is recorded per-message as the Block Reason.

A blocklist is "a list of IP addresses, email addresses, or domains known to ISPs or list providers for sending unsolicited or unwanted emails" (SendGrid retired the term "deny list" as its standalone glossary entry in favor of "blocklist"). Major ISPs and enterprises consult their own or third-party blocklists to filter mail. Landing on one is often the result of spam complaints, spam-trap hits, sudden volume spikes, or poor list hygiene on the IP — and on a shared IP it can be caused by another sender in the pool.

The separate IP Access Management lockout has nothing to do with blocklists: it happens when the allowlist doesn't include the IP you're connecting from (common with dynamic/residential IPs).

How do I fix a blocked SendGrid sending IP?

1. Read the Block Reason. In the SendGrid app go to Suppressions > Blocks (or the Email Activity feed). The Block Reason gives the exact rejection text, which usually names the blocklist or the receiving server's policy.
2. Confirm whether it's the IP or the domain. If the listing is against your sending domain rather than the IP, the domain's controller (you) must handle that delisting — SendGrid cannot.
3. Submit a delisting request to the right party:
4. Shared IP plan: Generally do nothing. SendGrid receives automatic notifications when a shared pool is listed and handles delisting on your behalf. That said, shared IPs carry higher deliverability risk than dedicated IPs — the same pool can be relisted again quickly if another sender on it triggers spam complaints, since you're sharing reputation with everyone else on the pool.
5. Dedicated IP plan: You submit the initial delisting request, because you alone control what that IP sends and are responsible for its reputation. SendGrid will assist if the listing service requires the IP administrator to act or the form is complicated. Open a SendGrid support ticket if you need help.
6. Never pay a delisting fee. SendGrid's guidance is explicit: legitimate blocklists accept delisting requests at no charge. If a service demands payment or says it doesn't accept delisting requests, don't bother — those lists are rarely used by real ISPs.
7. Clear individual recipient blocks. If a specific recipient is in Suppressions > Blocks, select it and Delete (or use the gear menu > Delete All) so SendGrid will attempt delivery to that address again.
8. Fix the underlying reputation so you don't get relisted: authenticate with SPF, DKIM, and DMARC, prune invalid/unengaged addresses, warm up volume gradually, and honor unsubscribes. A dedicated IP gives you more control over reputation (no noisy neighbors) but you own all the maintenance, and SendGrid recommends it as the more reliable option for critical, high-volume sending.

How do I fix the IP Access Management lockout?

If you're blocked from logging in to SendGrid itself, disabling or editing IP Access Management requires access you no longer have, so contact Twilio SendGrid support and be ready to prove identity and account ownership. To avoid this, always add your current IP before enabling the feature, and prefer static IPs — the allowlist holds up to 1,000 addresses.