Nuntly

Nuntly is a developer-first email service for sending transactional messages and handling replies through a REST API. It suits teams building email workflows into their products; the unified sending and inbound tools are its clearest advantage, though the free plan’s daily cap is restrictive.

Overview

Nuntly brings outbound email, inbound inboxes, replies, and delivery monitoring under one API. Developers can send individual or bulk email immediately or on a schedule, with or without templates. On the receiving side, custom inboxes group messages into threads, store messages, expose attachments, and support replies through an API.

The service reaches beyond basic send-and-forget delivery: its dashboard and webhooks surface delivery, opens, clicks, bounces, complaints, and inbound messages. Logs are retained for up to 30 days on the standard plans. That combination makes Nuntly a fit for product email workflows that need both replies and operational visibility, rather than a general-purpose campaign platform.

Key features

One API for sending and receiving

The REST API covers domains, API keys, webhooks, analytics, sending, receiving, and team members. TypeScript and Java SDKs include typed errors, pagination helpers, and built-in retries. This is a practical advantage for teams integrating email into an application, but it is less compelling for readers who chiefly want a visual marketing campaign tool.

Inbound email and agent workflows

Inbound messages can be organized into inboxes and threads, with namespaces, attachment access, inbound webhooks, and a Reply API. AI agents can use structured JSON, thread context, and memory scoped globally, by inbox, or by thread. Teams can run agent logic in their own infrastructure with Claude, GPT, Gemini, LangChain, LlamaIndex, or a custom pipeline. These options support custom reply workflows without requiring the agent logic to run in Nuntly.

Delivery visibility and controls

Webhooks report delivery, open, click, and bounce events in real time, with retries and replay. Filtering, exponential backoff, payload inspection, and cryptographic signature verification give developers useful control when building event-driven systems. Email authentication supports DKIM, SPF, and DMARC configuration. Nuntly says data is encrypted at rest with AES-256 and in transit with TLS 1.3, and that it is GDPR compliant with European hosting; it does not claim formal security certifications.

Pricing

Nuntly has a free plan and paid plans from €10/mo. The free tier requires no credit card, but its 3,000-email monthly allowance is further constrained by a 100-email daily cap. It includes one domain, one inbox, and 30-day data retention, making it suitable for low-volume evaluation or a small service—not steady, higher-volume sending.

Starter costs €10.00 per month and raises the allowance to up to 10K emails per month, with 10 domains, 10 inboxes, 30-day retention, email support, and Discord community support.

Scale costs €68.00 per month and supports up to 100K emails monthly, 1,000 domains, and 100 inboxes, with 30-day retention and email and Slack support. Dedicated IPs are an add-on. Its much larger capacity suits teams operating email across multiple products or domains, but is a substantial step up from Starter.

Enterprise has custom pricing, flexible sending volume, unlimited inboxes, configurable retention, priority support, and dedicated IPs as an add-on. It is aimed at organizations that need volume or retention arrangements beyond the fixed plans. Free, Starter, and Scale each specify 30-day retention; only Enterprise makes retention configurable.

Platforms

Nuntly is available through an API and on the web. The API is the core integration surface, while the web dashboard provides delivery analytics and monitoring. Its type-safe SDKs include documented TypeScript and Java clients.

Who it's for

Nuntly is best suited to developers and product teams that need transactional sending, inbound replies, and event-level visibility in the same service. Its thread-aware inboxes and agent integrations are especially relevant when an application needs to process and answer incoming email. Readers seeking a simpler outbound-only workflow or a broad consumer-facing email marketing platform should compare alternatives before choosing it.

Pros and cons

• Pros: Sending, inbound threads, and replies share one REST API, reducing the need to assemble separate services for those workflows.
• Pros: Webhook retries, replay, filtering, and signature verification provide useful safeguards for delivery-event integrations.
• Pros: The no-card free tier includes 3,000 emails per month and 30-day retention, with both an API and web dashboard.
• Cons: The free plan’s 100-email daily ceiling limits burst capacity even when monthly volume remains available.
• Cons: Dedicated IPs are add-ons on paid plans, so they are not included in the stated base prices.
• Cons: Enterprise uses custom pricing, and only that plan offers configurable data retention.

Alternatives

Transactional Email Software is a useful category starting point for comparing services around this core use case.

Choose Mailchimp instead if you want web and mobile platforms and a free plan built around contacts and audiences; its free allowance is 500 emails per month, 250 contacts, one audience, and one seat. Postmark is another API-and-web option, with a free plan capped at 100 emails per month and no overages. For a substantially larger free outbound allowance, Maileroo offers 3,000 outbound and 1,000 inbound emails monthly, plus two custom domains. MailerSend offers API access and a free plan with 500 emails per month, 100 daily API requests, one domain, and one template.

Twilio Segment, Reloop, Resend Broadcasts, and SMTP2GO are also alternatives to consider.

Verdict

Choose Nuntly if your product needs both transactional email and a way to receive, thread, reply to, and monitor messages through developer-facing tools. Its main strength is that those workflows sit together in one API, with capable webhook controls and agent integrations. Look elsewhere if the free daily cap is too low, you need dedicated IPs included in the base price, or your priority is a general email marketing platform.