Customer stories

Real teams.
Real outcomes.

From two-person startups to platforms serving millions — the teams that care about deliverability choose Sendbound.

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1B+

Emails delivered

99.97%

Avg. inbox placement

10k+

Active developers

<1 hr

Average migration

Trusted by teams at

Case studies

The numbers behind the names

Six teams, six problems, one platform. Here's exactly what happened.

RaycastDeveloper Tools

From 87% to 99.4% inbox placement in 7 days

How Raycast stopped losing developer emails and reclaimed their sending reputation

Raycast serves 200,000+ developers across 150 countries who depend on transactional email for password resets, team invites, and billing receipts. After years of fighting deliverability fires on their legacy provider, they migrated to Sendbound and watched inbox placement climb 12 points in the first week. No downtime. No re-engineering.

"Our engineers used to dread email tasks. Now they ask for them. Sendbound's API is genuinely a pleasure to work with — and the deliverability difference was immediate."
— Thomas L., CTO, Raycast

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99.4%Inbox placementup from 87%

12×Faster APIvs. legacy provider

45 minMigration timezero downtime

SchedlyScheduling & Calendaring

4.2M appointment emails a month, zero missed sends

How Schedly made appointment reminders so reliable they stopped getting asked about them

When you build a scheduling product, your email infrastructure is your product. A missed reminder equals a missed appointment equals a churn risk. Schedly migrated 4.2M monthly reminder and confirmation emails to Sendbound after their previous provider dropped nearly 3% of transactional sends during peak hours. Support ticket volume dropped 34% — entirely from "I never got my reminder" disappearing.

"We stopped getting "where's my reminder?" tickets the week we switched. That single change saved us more in support cost than Sendbound charges us per year."
— Priya M., Head of Engineering, Schedly

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4.2MEmails / monthzero drops

34%Fewer support ticketsfrom missed sends

99.96%Delivery ratesustained 6 months

Zignaturee-Signature & Contracts

Document signing emails that always arrive — and always convert

How Zignature turned email deliverability into a signing completion advantage

In the e-signature world, a document request that hits spam is a deal that doesn't close. Zignature processes 180,000 signing invitations per month across legal, real estate, and HR verticals. After switching from a shared-IP provider and adding custom DKIM per sender domain, their signing completion rate climbed 22% in 60 days. The emails simply started landing.

"We thought our completion rate problem was a UX problem. Turned out it was a deliverability problem. Sendbound fixed it before we even had to A/B test anything."
— Jordan K., CEO, Zignature

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+22%Signing completionin 60 days

180kInvitations / monthacross 6 verticals

< 2 sDelivery latencyP99

SupportlyCustomer Support

NPS response rate doubled — without changing a word of copy

How Supportly 2×'d their NPS response rate by fixing what was invisible

Supportly sends ticket confirmations, agent reply notifications, and NPS surveys. All three have to land. After struggling with a shared IP that kept getting flagged by enterprise spam filters, they moved to Sendbound with dedicated IPs. NPS response rates went from 6.1% to 14.3% in two months — not from better copy, but from emails that actually arrived.

"Our NPS open rate was fine — the problem was that half our sends weren't reaching inboxes. Sendbound fixed that, and our response rate doubled. It's not magic, it's infrastructure."
— Sam R., VP Product, Supportly

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14.3%NPS response rateup from 6.1%

3 flowsCritical email typesall migrated

2 moTime to full resultsfrom migration date

GuidezOnboarding & Product Tours

Trigger latency cut from 4–9 minutes to under 15 seconds

How Guidez rebuilt their activation funnel on Sendbound in three days

Guidez sends behavioral onboarding emails triggered by in-product actions. Timing is everything: an email about a feature the user just touched, sent 8 minutes later, converts. The same email sent hours later is noise. Their previous provider averaged 4–9 minutes of trigger latency. After migrating to Sendbound's transactional API, P95 latency dropped below 15 seconds. Activation rates improved 18% the first month.

"With Sendbound, our behavioral triggers actually behave. Sub-15-second latency on transactional sends completely changed what's possible in our onboarding sequences."
— Alex W., Co-founder, Guidez

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<15 sTrigger latencyP95 — down from 4–9 min

+18%Activation ratefirst month post-migration

3 daysFull migrationincluding template rebuild

MintlifyDeveloper Infrastructure

0 missed billing emails across 40,000 developers in 14 months

How Mintlify made high-stakes developer notifications completely reliable

Mintlify sends deployment alerts, invoice receipts, payment failure warnings, and security notifications. Missing a payment-failure email means involuntary churn. Missing a deployment failure means a developer's documentation site is down without them knowing. Mintlify chose Sendbound for its reliability guarantees, webhook audit trail, and dedicated IP infrastructure. Zero missed billing emails in 14 months of production.

"We have 40,000 developers who need to know when something goes wrong with their deploy. Sendbound is the layer we trust with that responsibility. It has never let us down."
— Cade H., CTO, Mintlify

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0Missed billing emails14 months running

40kActive developersacross 4 email flows

100%Audit trail coveragevia webhook events

What they say

In their own words

"We stopped getting 'where's my reminder?' tickets the week we switched. That change saved us more in support cost than Sendbound charges us per year."

Priya M.Head of Engineering, Schedly

"Sub-15-second trigger latency completely changed what's possible in our onboarding sequences. Activation improved 18% the first month."

Alex W.Co-founder, Guidez

"We have 40,000 developers who need to know when their deploy fails. Sendbound is the layer we trust with that. It has never let us down."

Cade H.CTO, Mintlify

"We thought our completion rate problem was UX. Turned out it was deliverability. Sendbound fixed it before we even had to A/B test anything."

Jordan K.CEO, Zignature

"Our engineers used to dread email tasks. Now they ask for them. Sendbound's API is genuinely a pleasure — and the deliverability difference was immediate."

Thomas L.CTO, Raycast

"Our NPS open rate was fine. The problem was half our sends weren't reaching inboxes. Sendbound fixed that and our response rate doubled."

Sam R.VP Product, Supportly

Real teams.Real outcomes.

The numbers behind the names

How Raycast stopped losing developer emails and reclaimed their sending reputation

How Schedly made appointment reminders so reliable they stopped getting asked about them

How Zignature turned email deliverability into a signing completion advantage

How Supportly 2×'d their NPS response rate by fixing what was invisible

How Guidez rebuilt their activation funnel on Sendbound in three days

How Mintlify made high-stakes developer notifications completely reliable

In their own words

Real teams.
Real outcomes.