--- title: "Reloop vs ZeptoMail (2026): Pricing, Features and Which to Choose" description: "Reloop vs ZeptoMail (now Zoho CPaaS) compared honestly: pay-as-you-go credits vs monthly plans, transactional-only rules, inbound and agent inboxes, campaigns, self-hosting, and how to switch." canonical: "https://reloop.sh/blog/reloop-vs-zeptomail" last-updated: "2026-10-25" --- # Reloop vs ZeptoMail (2026): Pricing, Features and Which to Choose > For the site documentation index, see [llms.txt](/llms.txt). Docs index: [llms-docs.txt](/llms-docs.txt). Marketing corpus: [llms-full.txt](/llms-full.txt). Docs corpus: [llms-full-docs.txt](/llms-full-docs.txt). Product skill: [skill.md](/skill.md). Prefer markdown URLs (append `.md`) when available. > Reloop vs ZeptoMail (now Zoho CPaaS) compared honestly: pay-as-you-go credits vs monthly plans, transactional-only rules, inbound and agent inboxes, campaigns, self-hosting, and how to switch. Source: https://reloop.sh/blog/reloop-vs-zeptomail Published: 2026-10-25 **ZeptoMail is one of the cheapest ways to send transactional email, and it's very good at exactly that one job.** Zoho sells it on prepaid credits with no monthly fee, it only allows transactional mail, and it recently became part of **Zoho CPaaS** alongside SMS, WhatsApp and voice. **Reloop costs a little more at high volume, but it also receives mail into real inboxes, runs campaigns and automations, and is open source, so you can host it yourself.** We build Reloop, so weigh this accordingly. Where ZeptoMail is the better pick, we say so. --- ## The 30-second comparison | | **Reloop** | **ZeptoMail (Zoho CPaaS)** | |---|---|---| | Pricing model | Monthly plans | Prepaid credits, no monthly fee | | Free tier | 3,000 / mo, 100 / day | First credit free (10,000 emails) | | 50,000 emails | **$10 / mo** | About $12.50 in credits | | 100,000 emails | $20 / mo | About $25 in credits | | Credits expire | n/a | After 6 months | | Marketing email | Yes (campaigns) | Not allowed | | Inbound email | Mailboxes with threads, API, MCP, IMAP | Not offered for receiving and storing mail | | Automations | Yes | No | | Dedicated IP | Included on Growth ($20) | Paid add-on (US, EU, IN) | | SMTP relay | Yes | Yes | | Open source / self-host | Yes (Apache 2.0) | No | ZeptoMail's model is on [Zoho's pricing page](https://www.zoho.com/zeptomail/pricing.html): one credit sends 10,000 emails, the first credit is free, and credits are valid for 6 months. The per-credit price is widely listed at **$2.50** and varies by region, so check the page for yours. Reloop's prices are on [reloop.sh/pricing](/pricing). --- ## ZeptoMail is now Zoho CPaaS If you've looked recently, you'll have noticed the change. Zoho's site now says "ZeptoMail is now Zoho CPaaS", built on the same email infrastructure and adding **SMS** (India only, in beta), **WhatsApp** and **voice**. The email product, API and SMTP relay are unchanged, and the API now lives at `cpaas.zoho.com`. That's a plus if you also want OTPs over WhatsApp or SMS from one vendor. If you only need email, it doesn't change much. --- ## Pricing at real volumes ZeptoMail is pay-as-you-go: you buy credits of 10,000 emails and spend them down. At the widely listed $2.50 per credit: | Monthly volume | Reloop | ZeptoMail (approx.) | Cheaper | |---|---|---|---| | 3,000 | $0 | $0 (free credit) | Tie | | 50,000 | $10 | $12.50 | Reloop | | 100,000 | $20 | $25 | Reloop | | 250,000 | $20 + $75 overage = $95 | $62.50 | **ZeptoMail** | | 1,000,000 | $20 + $450 overage = $470 | $250 | **ZeptoMail** | Being straight about it: **above roughly 150,000 emails a month, ZeptoMail is cheaper per email.** Below that, Reloop's flat plans win, and they include things ZeptoMail doesn't sell at all (inboxes, campaigns, automations, a dedicated IP on Growth). Two details matter with credits: - **They expire after 6 months.** Buying in bulk to save time can waste money if your volume drops. - **The free credit is one-off.** It's 10,000 emails to get started, not a monthly allowance. Reloop's 3,000 free emails reset every month. And if you self-host Reloop, there's no per-email fee at all. See [self-hosted email infrastructure](/blog/self-hosted-email-infrastructure) for what that really involves. --- ## Developer experience Both give you a REST API, an SMTP relay and official SDKs. **ZeptoMail** ```typescript const client = new SendMailClient({ url: "api.zeptomail.com/", token: process.env.ZEPTOMAIL_TOKEN!, }); await client.sendMail({ from: { address: "hello@acme.com", name: "Acme" }, to: [{ email_address: { address: "user@example.com", name: "Ada" } }], subject: "Welcome", htmlbody: "

Thanks for signing up.

", }); ``` **Reloop** ```typescript const reloop = new Reloop({ apiKey: process.env.RELOOP_API_KEY! }); const { response, emailError } = await reloop.mail.send({ from: "Acme ", to: "user@example.com", subject: "Welcome", html: "

Thanks for signing up.

", }); ``` | | Reloop | ZeptoMail | |---|---|---| | Recipient shape | `"user@example.com"` or an array of strings | `[{ email_address: { address, name } }]` | | Auth | `x-api-key` header | `Authorization: Zoho-enczapikey ` | | Templates | Sent by ID with `{{{variables}}}` | `template_key` or `template_alias` with `merge_info` | | Grouping sends | Domains and API keys | Mail Agents (per product, environment or team) | | Error format | `message`, `why` and `fix` | Error code and message | | SMTP | `smtp.reloop.sh`, API key as user and password | `smtp.zeptomail.com`, user `emailapikey` | ZeptoMail's **Mail Agents** are a nice touch: each one has its own tokens, domains, webhooks and stats, so you can keep staging and production, or two products, cleanly apart. Reloop's error shape is our one strong opinion. When a send fails, the error says **why** and **how to fix it**: ```json { "message": "Domain not found", "why": "The domain mail.acme.com was not found or is not authorized for your organization", "fix": "Ensure the domain is registered and verified in your dashboard" } ``` --- ## Transactional only vs everything in one place This is the biggest product difference. **ZeptoMail only allows transactional email.** Its terms say you must not use it for marketing, promotional mail or newsletters, and accounts that keep doing so get blocked. That's a deliberate choice that protects its deliverability, but it means you need a second tool (often Zoho Campaigns) for anything else. **Reloop covers both** while keeping them separate where it matters: - **Transactional API and SMTP** for receipts, resets and alerts. - **Contacts, groups and subscription channels**, with one suppression list across everything. - **Broadcast campaigns** with scheduling. - **Event-triggered automations**: call `reloop.automations.start` when a user signs up and run a sequence of delays, conditions and emails. See [welcome sequences that convert](/blog/welcome-email-sequences-that-convert). If you'll only ever send receipts and OTPs, ZeptoMail's restriction costs you nothing. If you'll want onboarding or product announcements later, it's a second vendor and a second suppression list. --- ## Receiving email and agent inboxes ZeptoMail is a sending service. Its webhooks report **opens, clicks and bounces**; we didn't find a feature for receiving mail on your domain and storing or threading it. **Reloop receives mail into mailboxes.** Messages are stored, threaded, spam-scored with Rspamd, and readable over the API, the [MCP server](/docs/integrations/ai-tools/mcp-server) or IMAP. You can reply in-thread with one call, and an `email.received` webhook pushes new mail to you. That matters for: - **AI agents that handle email.** Give an agent its own address and let it read and reply. See [build an AI agent that reads and replies to email](/blog/build-ai-agent-sends-emails). - **Support and reply handling** ("reply to this email to comment"). | | Reloop | ZeptoMail | |---|---|---| | Receive on your domain | Yes | No | | Stored mailboxes with threads | Yes | No | | Reply in thread via API | Yes | No | | MCP and IMAP access | Yes | No | | Delivery webhooks | Yes, signed (`Reloop-Signature`) | Yes (opens, clicks, bounces) | --- ## Deliverability Both run their own sending infrastructure and handle SPF, DKIM, bounces, complaints and suppression. - **ZeptoMail** keeps transactional mail on infrastructure that never carries marketing, which is the whole point of its policy. Dedicated IPs are a paid add-on in the US, EU and India regions. - **Reloop** runs its own MTA (KumoMTA) with per-domain throttling and automatic pauses when bounce or complaint rates spike, and includes a dedicated IP on Growth. Read [how bounce processing works](/blog/email-bounce-processing-automation). Either way, your own domain setup matters more than the provider. Check yours with our free [auth checker](/tools/auth-checker) and [blocklist checker](/tools/blocklist-checker). --- ## Self-hosting and lock-in ZeptoMail is hosted-only, on Zoho's data centers. Reloop is Apache 2.0: start on Reloop Cloud, move to your own server later with the [one-command installer](/self-host) or [Coolify](/blog/reloop-coolify-setup), and point the SDK's `baseUrl` at your instance. Nothing else in your code changes. --- ## Where ZeptoMail is the better choice - **You send a lot of purely transactional mail.** Above about 150k emails a month, credits are cheaper than Reloop's plans. - **Your volume is spiky or seasonal.** No monthly fee means quiet months cost nothing, as long as you use credits within 6 months. - **You're already on Zoho** (CRM, Desk, Books) and want one vendor and one bill. - **You want WhatsApp, SMS or voice** from the same platform as email. ## Where Reloop is the better choice - **You're under about 150k emails a month**, where Reloop's flat plans are cheaper. - **You need to receive email**, especially for AI agents or support. - **You want campaigns and automations** without a second tool. - **You need open source or self-hosting** for compliance or data residency. --- ## Switching from ZeptoMail to Reloop 1. **Add your domain in Reloop** and publish the DKIM record (`reloop._domainkey`). Merge `include:reloop.sh` into your existing SPF record; don't add a second one. 2. **Swap the client.** Replace `client.sendMail` with `reloop.mail.send`. Flatten recipients from `{ email_address: { address } }` to plain strings, and rename `htmlbody` → `html`, `textbody` → `text`. 3. **Move templates.** Recreate them in Reloop and change placeholders to triple braces: `{{{user_name}}}`. Values you passed in `merge_info` become template variables. 4. **Map Mail Agents.** Use separate domains or API keys where you had separate agents. 5. **Point webhooks** at a new handler. Reloop events are `email.delivered`, `email.bounced`, `email.complained` and so on, signed with HMAC-SHA256 in the `Reloop-Signature` header. 6. **Ramp traffic** from 10% to 100% over a week or two. Use up remaining credits first if they're close to expiring. Our [SendGrid migration guide](/blog/migrating-from-sendgrid) covers the traffic-split flag and suppression import in more detail. --- ## FAQ At high volume, yes. At the widely listed $2.50 per 10,000 emails, ZeptoMail is cheaper above roughly 150k emails a month. Below that, Reloop's $10 (50k) and $20 (100k) plans cost less. No. ZeptoMail's terms only allow transactional email and accounts that keep sending marketing mail get blocked. Reloop supports both transactional email and campaigns. It's now part of Zoho CPaaS, which adds SMS, WhatsApp and voice to the same email infrastructure. The email API and SMTP relay still work the same way. Yes, 6 months after purchase. Reloop's plans are monthly, with $0.50 per 1,000 emails above your plan's allowance. Its docs describe sending, templates and delivery webhooks, not inbound mailboxes. Reloop receives mail into threaded inboxes you can read over the API, MCP or IMAP.