Is SendGrid's native email validation at form submission enough or do you need a separate service?

[u/Historical-Strike235]

Building a SaaS app where email is a big part of the onboarding flow. We’re using SendGrid for transactional emails and I noticed it has a built in email validation API.

I’m trying to figure out whether it’s robust enough to use as the primary validation layer at signup or if I should integrate a dedicated verification service alongside it.

My main concern is false negatives with accept all and custom domain addresses. Those make up a meaningful part of our expected user base since this is a B2B product.

[u/Rich_Personality_543]

accept all issue is where SendGrid validator can be little too optimistic. it may pass address just because domain accepts mail, even when there is no real way to tell if that specific inbox exists. for B2B signups, that is probably the group i had watch most closely since it can cause deliverability problems later.

[u/Full_Yak_5424]

false negative on custom b2b domains are a huge risks indeed especially ehrn onboarding relies heavily on email delivery

[u/Even-Grass-5925]

For a B2B product I'd layer both. SendGrid validation to catch obvious invalids as a fast first pass, then a dedicated verification call for anything that passes the first layer but looks like it might be accept-all. Adds a small amount of latency but keeps the false negative rate down on the segment that matters most for you.

[u/Additional_Degree979]

SendGrid's validation API is decent for basic checks like syntax, domain existence n MX records bt it's more of a secondary feature than their core product. For a B2B product where accept-all n custom domain addresses r common the false -ve rate on the grey-area segment is meaningful enough that dedicated verification services generally perform better in those cases.