Private beta
Email that leaves from your customers' own domains.
Postlysend is the sending layer for products that send mail on someone else's behalf. Your customers connect their domain, you call one API, and the message is signed and delivered as theirs not yours.
We'll email you when your account is ready. Nothing else.
Or write to us at support@postlysend.com
What you get
Send from customer domains
Every customer authenticates their own sending domain before a single message goes out. DKIM signing and a matching return path mean the mail aligns to them, and their DMARC policy passes.
Reputation is per account
Each customer sends under its own account, with its own reputation metrics and its own suppression list. A bad campaign in one account doesn't reach into another.
Delivery data you can act on
Per-message events for accepted, delivered, bounced, and complained, available in the dashboard and on a webhook. No guessing why something didn't arrive.
Connecting a domain
Four steps to get a customer sending.
Add the domain
Your customer enters the domain they want to send from. We generate a DKIM key pair and a dedicated return path subdomain for them.
Publish the records
We hand back the exact DNS entries to add — a DKIM CNAME, an SPF include, and the MX and TXT for the return path. Copy, paste, save.
We check and confirm
Postlysend polls DNS until every record resolves, then marks the domain verified. If something's wrong, we say which record and what's missing.
Send
Call the API or point an SMTP client at us. Unverified domains can't send, so nothing goes out unsigned.
How we run the platform
How we protect deliverability.
Each customer authenticates their own sending domain with DKIM, SPF, and DMARC before we let them send. Reputation, suppression, and sending thresholds are tracked and enforced per account. Accounts that exceed our thresholds are suspended pending review.
Consent is required
Recipients must have asked to hear from the customer sending to them. Purchased, rented, scraped and appended lists are prohibited and grounds for immediate suspension.
Bounces and complaints suppress instantly
Hard bounces and spam complaints are written to the sending account's suppression list as they arrive. Suppressed addresses can't be sent to again.
Accounts pause automatically
Sending halts pending review when an account passes 0.1% complaints or 5% hard bounces. The threshold applies per account, so one sender's problem stays theirs.
Unsubscribing actually works
Bulk mail carries one-click unsubscribe headers as well as a visible link, and opt-outs are honoured on receipt rather than on a schedule.
We know who signs up
New accounts are reviewed before sending is enabled. We check the business, the domain, and what they intend to send.
Encrypted in transit
TLS on delivery wherever the receiving server supports it, and enforced TLS available for accounts that require it.
Pricing
Simple pricing per sending account.
Starter
$49 / month
For teams onboarding their first customers to send from their own domains.
- Up to 5 verified sending domains
- 25,000 emails per month included
- Per-account suppression & reputation
- Delivery webhooks and dashboard
- Email support
Growth
$199 / month
For products with a growing base of customers sending real volume.
- Up to 50 verified sending domains
- 250,000 emails per month included
- Overage at $0.50 per 1,000 emails
- Enforced TLS, dedicated IPs available on request
- Priority support
Scale
Custom
For platforms sending on behalf of hundreds or thousands of customers.
- Unlimited verified sending domains
- Volume-based pricing
- Dedicated IP pools available on request
- SLA and DPA on request
- Named account contact
Prices in USD, billed monthly or annually. Beta customers receive founding pricing for the first 12 months. Fair-use limits apply — see the Acceptable Use Policy.
Get on the list for the private beta.
We're onboarding a small number of teams at a time so we can watch delivery closely for each one. Tell us what you're building and we'll be in touch.
We'll email you when your account is ready. Nothing else.
Or write to us at support@postlysend.com
About
About Postlysend
Postlysend is email sending infrastructure for software companies whose customers need to send mail from their own domains — invoicing tools, CRMs, booking systems, help desks, anything where the message should look like it came from the business using the product rather than the product itself.
Building that properly is more work than it looks. You need per-customer DKIM keys, a return path that aligns for DMARC, a DNS verification flow your customers can actually follow, suppression lists that don't leak between accounts, and a way to stop one careless sender from damaging delivery for everyone else. Most teams discover this after their first deliverability incident.
How we think about the work
Whether mail reaches an inbox depends more on whether the recipient asked for it than on anything technical. We won't take on senders who treat that as a formality, even if it costs us volume.
Every customer has their own suppression list and their own bounce and complaint thresholds. We track sending health at the account level, and we pause accounts that slip before the problem grows into a delivery issue for anyone else.
Email fails quietly. A message that ends up in spam produces no error, so we tell you what happened to each one, and we tell you clearly when a domain isn't configured properly rather than accepting it and letting the mail fail later.
Company details
Inaflow Inc.
Business Number 734352032
503 Sage Hill Drive NW
Calgary, Alberta T3R 0S4, Canada
Contact
Contact us
General, support, and privacy
Sales, product questions, support, and privacy or data requests. One inbox, triaged on receipt.
support@postlysend.comReporting abuse
If you received unwanted mail delivered by Postlysend, forward it to us with full headers. We investigate every report and don't disclose the reporter's identity to the sender.
abuse@postlysend.comPostal address
Inaflow Inc.
503 Sage Hill Drive NW
Calgary, Alberta T3R 0S4
Canada
If you received mail you didn't ask for
Postlysend delivers mail on behalf of its customers, so the sender is usually a business you have a relationship with rather than us. Every message we deliver carries an unsubscribe link, and using it stops that sender immediately.
If unsubscribing doesn't work, or you never gave that sender permission in the first place, forward the message with full headers to abuse@postlysend.com. We investigate every report and suspend accounts that send without consent.
Acceptable use
Acceptable Use Policy
This policy forms part of the Terms of Service. Breaking it is grounds for suspension or termination without notice and without refund. We enforce it, including against paying customers.
1. Consent is mandatory
You may only send mail to recipients who have given you permission to contact them at the address you are sending to. Permission must be recorded, and you must be able to produce evidence of it on request — the date, the source, and the method by which it was given.
The following are expressly prohibited as sources of recipient addresses:
- Purchased, rented, leased, or otherwise acquired lists
- Addresses harvested or scraped from websites, directories, social networks, or public records
- Addresses obtained through appending, enrichment, or matching services
- Addresses guessed, generated, or derived from a pattern
- Lists transferred from a third party, including lists acquired with a business
Consent does not transfer between senders, brands, or products. Someone who subscribed to one of your services has not consented to hear from another.
2. Domain authentication
You must verify each sending domain before using it. Verification requires publishing the DKIM, SPF, and return path records we issue. We do not permit sending from domains you do not control, and we do not permit sending from free mailbox domains such as gmail.com in the From header.
3. Unsubscribing
Every commercial or bulk message must contain a clear, working unsubscribe mechanism, and bulk mail must include one-click unsubscribe headers (RFC 8058). Opt-out requests must be honoured immediately and permanently. You may not require a login, a reason, a fee, or any further step to unsubscribe.
4. Content and conduct
You may not use Postlysend to send, facilitate, or promote:
- Phishing, spoofing, credential harvesting, or any message impersonating another person or organisation
- Malware, ransomware, or links to malicious payloads
- Child sexual abuse material, or any content that sexualises minors
- Harassment, threats, incitement to violence, or hate speech targeting protected characteristics
- Fraudulent offers, pyramid or Ponzi schemes, fake invoices, or advance-fee scams
- Cryptocurrency promotion, pump-and-dump schemes, or unregistered securities offerings
- Unlicensed pharmaceuticals, controlled substances, or counterfeit goods
- Sexually explicit material, escort services, or gambling where prohibited by the recipient's jurisdiction
- Content that infringes copyright, trademark, or other intellectual property rights
- Anything unlawful in the sender's or recipient's jurisdiction
You also may not obscure the origin of a message, forge headers, or use a reply-to address you do not monitor.
5. Sensitive data
Do not transmit full payment card numbers, card verification values, full bank account numbers, government identity numbers, or protected health information through the service. Email is not an appropriate channel for this data, and sending it puts both of us in regulatory scope we have not agreed to.
6. Technical limits
- Do not exceed the sending rate or volume assigned to your account, or attempt to circumvent it
- Do not open multiple accounts to spread volume, evade limits, or evade a suspension
- Do not send to addresses on your suppression list, or attempt to remove valid suppression entries
- Do not use the service for load testing, scanning, or any purpose other than sending mail your recipients expect
- Do not share API keys outside your organisation or embed them in client-side code
7. Deliverability thresholds
We monitor bounce and complaint rates continuously at the account level. Sending is paused automatically, pending review, when an account exceeds:
- 0.1% spam complaints measured over a rolling window
- 5% hard bounces measured over a rolling window
A pause is not a punishment; it is how we stop a list problem becoming a delivery problem for you and for every other sender on the platform. We will tell you what triggered it and what we need to see before sending resumes. Repeated pauses lead to termination.
8. Suppression
Hard bounces and spam complaints are added to your account's suppression list automatically and cannot be sent to again through your account. Suppression is scoped to your account — it does not affect other customers, and other customers' suppression does not affect you.
9. If you send on behalf of others
If your own product uses Postlysend to send mail for your customers, you are responsible for their conduct as if it were your own. You must impose obligations on them at least as strict as this policy, verify their sending domains, screen them before enabling sending, and act on abuse reports we forward to you.
10. Reporting abuse
Anyone may report suspected abuse to abuse@postlysend.com. Include the full message headers. We review every report. We do not disclose the reporter's identity to the sender.
11. Enforcement
Depending on severity and history, we may: request evidence of consent; throttle or pause sending; suspend an account; or terminate it. Serious violations — phishing, malware, illegal content, deliberate evasion — result in immediate termination and, where appropriate, referral to law enforcement.
We may act without prior notice where delay would cause harm to recipients, to other customers, or to the platform's reputation.
12. Changes
We may update this policy as sending standards and mailbox provider requirements change. Material changes will be announced by email to account administrators at least 14 days before they take effect. Continued use after that date constitutes acceptance.
Terms
Terms of Service
These Terms govern your access to and use of the Postlysend service operated by Inaflow Inc. ("Postlysend", "we", "us"). By creating an account or sending mail through the service, you agree to them. If you are agreeing on behalf of an organisation, you confirm you have authority to bind it.
1. The service
Postlysend provides an API and SMTP relay for sending email, together with domain authentication, delivery event data, and suppression management. We may change, add, or remove features. Where a change materially reduces functionality you rely on, we will give at least 30 days' notice by email.
2. Accounts
You must provide accurate registration details and keep them current. You are responsible for all activity under your account and for the security of your API keys and credentials. Tell us promptly at support@postlysend.com if you believe a credential has been compromised.
New accounts are reviewed before sending is enabled. We may decline to open an account, or require additional information about your business and intended use, at our discretion.
3. Acceptable use
Your use of the service is subject to the Acceptable Use Policy, which is incorporated into these Terms. You are responsible for the content of every message sent through your account, and for ensuring you have permission to contact every recipient.
4. Sending on behalf of your own customers
If you use Postlysend to send mail for your customers, you remain responsible for their conduct. You must bind them to terms at least as protective as these, verify their sending domains, and respond to abuse reports we pass to you within two business days.
5. Fees and payment
Paid plans are billed monthly or annually in advance, with usage above plan allowances billed in arrears. Fees are exclusive of taxes, which you are responsible for. Payment is due on receipt of invoice. We may suspend the service on non-payment after giving notice.
You may cancel at any time, effective at the end of the current billing period. Fees already paid are not refundable except where required by law.
6. Your data
You retain all rights in the content you send and the recipient data you upload. You grant us the limited licence necessary to transmit, store, process, and deliver it, and to produce aggregated statistics that do not identify you or your recipients.
Our handling of personal data is described in the Privacy Policy. Where we process personal data on your behalf, a Data Processing Agreement is available on request.
7. Suspension and termination
We may suspend or terminate your account, in whole or in part, if you breach these Terms or the Acceptable Use Policy, if your sending threatens the deliverability or reputation of the platform, if required by law, or on non-payment.
Where circumstances allow, we will give notice and an opportunity to fix the problem. Where they do not — phishing, malware, illegal content, or sending that presents an immediate risk — we will act first and explain afterwards.
On termination, your right to use the service ends immediately. We will retain your message logs and account data for 30 days, during which you may request an export, after which they are deleted.
8. Availability
We aim for high availability but do not guarantee uninterrupted service on plans without a written service level agreement. Email delivery depends on receiving mail servers we do not control; we cannot guarantee that any message will be accepted or placed in an inbox.
9. Warranties
The service is provided "as is". To the fullest extent permitted by law, we disclaim all implied warranties, including merchantability, fitness for a particular purpose, and non-infringement.
10. Limitation of liability
To the fullest extent permitted by law, neither party is liable for indirect, incidental, special, consequential, or punitive damages, or for lost profits, revenue, data, or goodwill. Our total aggregate liability arising from or relating to these Terms is limited to the fees you paid us in the twelve months preceding the event giving rise to the claim.
Nothing in these Terms limits liability for death or personal injury caused by negligence, for fraud, or for anything else that cannot lawfully be limited.
11. Indemnity
You will indemnify us against claims, damages, and reasonable costs arising from the content you send, your breach of these Terms or the Acceptable Use Policy, or your violation of any law or third-party right.
12. Changes to these Terms
We may update these Terms. Material changes will be notified by email to account administrators at least 30 days before they take effect. Continued use after that date constitutes acceptance.
13. Governing law
These Terms are governed by the laws of Alberta, Canada, and the courts of Alberta, Canada have exclusive jurisdiction over any dispute, without regard to conflict of law rules.
14. Contact
Inaflow Inc.
503 Sage Hill Drive NW
Calgary, Alberta T3R 0S4, Canada
support@postlysend.com
Privacy
Privacy Policy
This policy explains how Inaflow Inc. ("Postlysend") handles personal data. It covers our website, our marketing, and the Postlysend service.
1. Two different roles
We handle personal data in two capacities, and it matters which:
As a controller, for data about our own customers and website visitors — the people who sign up for accounts, email us, or join the waitlist. This policy governs that data.
As a processor, for the recipient data our customers send through the service. We process it on their instructions and for no other purpose. If you received an email delivered by Postlysend and want to know why you were contacted, the sender is the controller — contact them, or write to support@postlysend.com and we will pass your request on.
2. What we collect as controller
- Account data: name, work email, company name, billing address, and authentication details
- Billing data: plan, invoices, and payment records. Card details are handled by our payment processor and never stored by us
- Usage data: API requests, sending volumes, error rates, and login events
- Support correspondence: the content of messages you send us
- Website data: IP address, browser type, pages viewed, and referrer
3. What we process as processor
To deliver mail for our customers we process: recipient email addresses, message content and attachments, delivery events (accepted, delivered, bounced, deferred, complained), and where the customer enables it, open and click events.
4. Why we process it
- To provide the service and deliver mail (performance of a contract)
- To bill you and keep financial records (contract and legal obligation)
- To detect abuse, prevent fraud, and protect deliverability (legitimate interests)
- To answer support requests (contract and legitimate interests)
- To send product and marketing email (consent, withdrawable at any time)
- To comply with law and respond to lawful requests (legal obligation)
5. How long we keep it
- Message content: 30 days, then deleted
- Delivery event metadata: 90 days
- Suppression list entries: for the life of the account, because deleting them would allow mail to reach people who opted out
- Account and billing records: for the life of the account plus the period required by tax law
- Website analytics: 12 months
6. Who we share it with
We use a small number of subprocessors to run the service. A current list is available on request and we give notice before adding a new one.
- Amazon Web Services: hosting and email delivery infrastructure
- Stripe and Paystack: billing
We do not sell personal data. We do not share it for anyone else's advertising. We disclose data to authorities only where legally compelled, and we tell the affected customer unless prohibited from doing so.
7. Security
We encrypt data in transit with TLS and at rest. Access to production systems is limited to staff who need it, protected by multi-factor authentication, and logged. API keys are stored hashed. We will notify affected customers without undue delay if a breach affects their data.
8. Your rights
Depending on where you live, you may have the right to access, correct, delete, restrict, or object to our processing of your personal data, and to receive it in a portable format. To exercise any of these, write to support@postlysend.com. We respond within 30 days.
You may unsubscribe from our marketing at any time using the link in any message. You may also complain to your local data protection authority.
9. Cookies
We use cookies that are strictly necessary to run the site and keep you signed in. You can clear or block cookies in your browser, though the dashboard will not work properly without the necessary ones.
10. Children
The service is for businesses. We do not knowingly collect personal data from anyone under 16. If you believe we have, write to us and we will delete it.
11. Changes
We will post any update here and change the date at the top. Material changes will be emailed to account administrators in advance.
12. Contact
Inaflow Inc.
503 Sage Hill Drive NW
Calgary, Alberta T3R 0S4, Canada
support@postlysend.com