Short answer: transactional email is sent to one person because of something they did or need: password resets, receipts, order updates, delivery notices and OTP codes. Marketing email is sent to many people at once to promote something: newsletters, offers and announcements. Keep them separate, because if your newsletters attract spam complaints, you do not want login codes and receipts to stop arriving.
Many businesses send both kinds of email from the same place without thinking about it, until one bad campaign means customers stop receiving their OTP codes. This guide explains the difference, why separation matters, and what each type needs to work well.
The difference at a glance
| Transactional | Marketing | |
|---|---|---|
| Example | "Your order #1042 is confirmed" | "Our December sale starts today" |
| Sent to | One person | Many people |
| Triggered by | An action or event | You, on a schedule |
| Expected by the recipient | Yes, they are waiting | Only if they subscribed |
| Urgency | Often urgent (codes, receipts) | Rarely urgent |
| Unsubscribe link | Not required | Required |
| Consent | Part of the service relationship | Clear opt-in needed |
| Typical complaint rate | Very low | Higher |
| Priced by (SiloLobby) | Emails a month | Contacts |
Examples of transactional email
- Account sign-up confirmations and welcome emails
- Password resets and one-time passcodes (OTPs)
- Order confirmations, invoices and receipts
- Shipping and delivery updates
- Booking and appointment confirmations
- Security alerts (new login, password changed)
- Account statements and important service notices
Examples of marketing email
- Newsletters
- Sales and promotions
- Product launches and announcements
- Event invitations
- Re-engagement campaigns ("we miss you")
Why separation matters
Mailbox providers such as Gmail and Outlook judge each sender's reputation from bounces, spam complaints and engagement. Marketing email naturally gets more complaints and unsubscribes than receipts and codes.
If both share one reputation:
- a newsletter sent to an old list can trigger bounces and complaints,
- your sending reputation drops,
- password resets and OTP codes start landing in spam or arriving late,
- customers cannot log in or complete purchases.
At SiloLobby transactional and marketing sending are separate products with separate tracking, so one cannot damage the other.
What transactional email needs
- Speed and reliability: the person is waiting for the code or receipt.
- SMTP or API access so your website or app sends automatically. See how to send email from your website or app.
- A verified sending domain with SPF, DKIM and DMARC.
- Delivery logs to answer "I didn't get my code".
- Bounce and complaint handling so you stop sending to dead addresses.
SiloLobby transactional plans start free, with paid plans from ₦32,000/month for 50,000 emails a month.
What marketing email needs
- Consent: only email people who asked to hear from you.
- List cleaning to remove broken, mistyped and disposable addresses before you send.
- Unsubscribe links in every email, including the one-click unsubscribe header that Gmail and Yahoo require for bulk senders.
- Sending in batches rather than all at once.
- Content that inboxes trust: honest subjects, real links and your business address.
SiloLobby marketing plans start free, with paid plans from ₦32,000/month for 2,500 contacts. Read email marketing in Nigeria: build a list legally.
Grey areas
Some emails mix both. A good rule: if the main purpose is to complete something the person asked for, it is transactional; if the main purpose is to sell, it is marketing.
- An order confirmation with a small "you may also like" section is transactional, as long as the promotion is minor.
- A "your cart is waiting" reminder sits in between; send it carefully and let people opt out.
- A "new features" announcement to all users is marketing.
Using separate addresses
Use different sending addresses (or subdomains) for each type, for example orders@yourshop.com.ng for receipts and news@yourshop.com.ng for newsletters. It helps customers recognise each kind of email and keeps reporting clear.
Best practices for transactional emails
- Send immediately. Codes and receipts lose value with every minute of delay.
- Make the purpose obvious in the subject: "Your login code", "Receipt for order #1042".
- Keep the design simple and text readable on phones.
- Use a recognisable sender name and a reply address that someone reads.
- Include the key details (order number, amount, date) so customers can find the email later.
- Do not hide marketing inside transactional emails; keep any promotion small.
Best practices for marketing emails
- Send only to subscribers who opted in.
- Promise and deliver: send what people signed up for, as often as you said.
- Segment your list by interest or location for more relevant emails.
- Test subject lines and content on a small group first.
- Watch complaints and unsubscribes, and adjust.
How to set up both at SiloLobby
- Transactional: create an SMTP or API sending account, verify your domain, and connect your website or app. See how to send email from your website or app.
- Marketing: create a marketing account, import your consented contacts (they are cleaned automatically), write your campaign with the built-in content checker, and send in safe batches.
Both start with a free plan, so you can set everything up before paying.
Measuring success
| Type | Key measures |
|---|---|
| Transactional | Delivery rate, delivery speed, bounces, support tickets about missing emails |
| Marketing | Opens, clicks, conversions, unsubscribes, complaints |
If transactional delivery problems appear, check authentication (SPF, DKIM, DMARC) and your sending logs first.
Choosing the right plan
Transactional plans are priced by emails sent each month. Start on the free plan while you connect your website or app, then move to a paid plan, such as Pro 50K at ₦32,000/month for 50,000 emails, as volume grows.
Marketing plans are priced by the number of contacts on your list. Start free, then choose the plan that fits your list, for example Marketing 2.5K at ₦32,000/month.
You can run both side by side, each with its own reputation and reports.
Consent and the law
Transactional emails are part of providing your service, so customers generally expect them. Marketing emails need a lawful basis, usually consent, under the Nigeria Data Protection Act 2023, and every marketing email must let people unsubscribe easily. Keeping the two separate also makes it easy to honour unsubscribes without stopping the receipts and notices customers still need.
Quick test: which kind is this email?
Ask: "Would the customer be confused or harmed if this email did not arrive?" If yes (a receipt, code or delivery update), it is transactional. If no (a promotion or newsletter), it is marketing and needs consent and an unsubscribe link.
Summary
Transactional email is expected, individual and urgent; marketing email is promotional, bulk and needs consent. Send them through separate channels so newsletter complaints never block your receipts and login codes. SiloLobby offers both as separate products, each with the safeguards it needs.