Terms of Service

Effective date: June 1, 2026 · Last updated: June 30, 2026

These Terms of Service ("Terms") govern your access to and use of Unbox, the mail platform at unbox.im, operated by Zeptun Intelligence Limited (Hong Kong SAR). In these Terms, "Unbox," "we," "us," and "our" refer to Zeptun Intelligence Limited (Hong Kong SAR) as the operator of the Unbox platform. By creating an account or using the service, you agree to these Terms.

Service description

Unbox provides domain inbox hosting and management, optional external account connection, team collaboration features, and AI-assisted triage. Outbound delivery is provided through our HTTP API and optional SMTP submission for transactional mail only (see below). We reserve the right to modify features with reasonable notice to paid subscribers.

Outbound mail — API and SMTP (transactional only)

Unbox's HTTP API (POST /v1/email) and optional SMTP submission are intended exclusively for transactional email — messages triggered by a user action, purchase, security event, or operational workflow. Unbox is not a newsletter, marketing automation, or bulk promotional mail service.

Permitted transactional sends include

• Account verification, password resets, and security alerts
• Order confirmations, receipts, shipping updates, and payment notices
• Notifications triggered by a specific user or system event
• Team and workspace messages (invites, assignments, internal alerts)

Prohibited sends include

• Newsletters, promotional campaigns, or broadcast marketing
• Cold outreach or mail to purchased, scraped, or non-consenting lists
• Affiliate spam, phishing, or deceptive content
• Any attempt to bypass recipient caps, rate limits, or plan quotas

Rate limits and abuse controls

To protect recipients, our infrastructure partners, and your domain reputation, outbound API and SMTP traffic is subject to technical and policy limits, including:

• Recipients per message: Up to 50 total (To + Cc + Bcc combined)
• Unique recipients per day: Up to 1,000 per workspace
• Send request rate: Up to 10 API or SMTP submissions per minute per domain
• Plan outbound quota: Monthly send limits on your subscription still apply

These rules are part of our Acceptable Use Policy. Automated enforcement is live on the web composer, HTTP API, and SMTP submission. Accounts that send marketing or bulk mail, or otherwise abuse sending infrastructure, may be throttled, suspended, or terminated.

We monitor deliverability signals. Sustained bounce rates above 3% or complaint rates above 0.1% may trigger a temporary send pause or manual review.

Full privacy and data-protection context is in our Privacy Policy and GDPR Statement.

Account responsibilities

You are responsible for maintaining the security of your account credentials and for all activity under your account. You must provide accurate registration information and keep it current. You must be at least 18 years old to use Unbox. You are responsible for ensuring that mail sent through your domains complies with applicable law and these Terms, including obtaining any consent required for the specific messages you send.

Acceptable use

You agree not to use Unbox to:

• Send spam, phishing, unsolicited bulk email, or marketing newsletters through our API or SMTP
• Use the API or SMTP for promotional campaigns, cold outreach, or purchased mailing lists
• Distribute malware or engage in fraudulent activity
• Violate applicable laws or third-party rights
• Attempt to gain unauthorized access to our systems or other users' accounts
• Resell or sublicense the service without written permission
• Circumvent rate limits, recipient caps, DNS verification, or send blocks

We may throttle, suspend, or terminate accounts that violate acceptable use, damage deliverability, or pose abuse risk to our platform or upstream mail providers.

Domain and DNS

You retain ownership of domains you connect to Unbox. You are responsible for configuring DNS records at your registrar. We provide guidance and verification tools but do not operate your DNS unless explicitly agreed in a separate contract. Outbound sending through API or SMTP requires completed domain authentication (SPF, DKIM, DMARC, and related records) as shown in your Domains dashboard.

Billing and subscriptions

Paid plans renew automatically unless cancelled before the renewal date. Fees are non-refundable except as required by law or stated in our refund policy. We may change pricing with 30 days' notice to existing subscribers.

Free plan

New accounts start on the Free plan ($0) with full hosted-mail AI — no time limit and no credit card required. Upgrade to a paid plan anytime when you need more domains, send volume, or storage.

Intellectual property

Unbox retains all rights to the platform, software, and branding. You retain all rights to your mail content and data. You grant us a limited license to process your data solely to provide the service.

Disclaimer of warranties

Unbox is provided "as is" without warranties of any kind. We do not guarantee uninterrupted or error-free service. Email delivery depends on factors outside our control including recipient server policies.

Limitation of liability

To the maximum extent permitted by law, Unbox shall not be liable for indirect, incidental, special, or consequential damages. Our total liability for any claim shall not exceed the amount you paid us in the twelve months preceding the claim.

Termination

You may cancel your account at any time from Settings. We may terminate accounts for material breach of these Terms, including misuse of outbound API or SMTP. Upon termination, you may export hosted mail data within 30 days where available.

Governing law

These Terms are governed by and construed in accordance with the laws of the Hong Kong Special Administrative Region ("Hong Kong"), without regard to its conflict-of-law rules. For your contractual relationship with Unbox, Hong Kong law is the primary governing law and applies to the interpretation and enforcement of these Terms, except where mandatory law in your jurisdiction requires otherwise.

If you are in the European Economic Area, the United Kingdom, Switzerland, or another territory where Zeptun Intelligence Limited (Hong Kong SAR) provides the service, mandatory data-protection or consumer-protection rules may also apply to the extent they cannot be waived by contract. That includes the EU General Data Protection Regulation (GDPR) and similar frameworks described in our Privacy Policy and GDPR Statement. Where mandatory local law gives you rights or remedies that conflict with these Terms, those mandatory provisions prevail to the minimum extent required by applicable law.

Contact

Questions about these Terms: legal@unbox.im