--- title: "Enterprise SMTP Relay Built for Complex Requirements | OutboundSMTP" description: "When other providers focus only on volume, OutboundSMTP excels at delivering specialized solutions for your unique email challenges. Dedicated IPs, advanced authentication, and white-glove support." image: "https://outboundsmtp.com/images/og-default.png" canonical: "https://outboundsmtp.com/" --- Trusted by 40,000+ businesses # Enterprise SMTP Relay Built for Complex Requirements When other providers focus only on volume, we excel at delivering specialized solutions for your unique email challenges. - Dedicated IPs with warming assistance - Sub-second delivery, 99.9% uptime SLA - DKIM, SPF & DMARC fully managed - White-glove setup by delivery experts [ Try 1,000 Free Credits → ](https://insight.iljmp.com/4/smtp-free) [ Talk to an Expert ](/contact-us/) smtp-config.sh ``` # SMTP Configuration SMTP_HOST=smtp.outboundsmtp.com SMTP_PORT=587 SMTP_USER=your-api-key SMTP_TLS=required # Or use the API curl -X POST \ https://api.outbound.mailhop.org/v1/send \ -H "Authorization: Bearer API_KEY" \ -H "Content-Type: application/json" \ -d '{"to":"user@example.com"}' ``` Trusted across industries Enterprise SaaS E-Commerce Education Finance Healthcare Built for IT Professionals ## What Makes an Enterprise SMTP Relay Reliable? ### Dedicated IPs Full control over your sending reputation with dedicated IP addresses. IP warming assistance and custom PTR records included. ### Sub-Account Management Manage multiple applications with separate API keys, individual usage tracking, and custom sending limits per sub-account. ### Advanced Authentication Automatic DKIM signing, SPF record management, and DMARC alignment support. Custom MAIL FROM domains for full control. ### High Performance 99.9% uptime SLA with sub-second delivery times. Multi-region infrastructure ensures your emails arrive on time, every time. ### Real-time Analytics Comprehensive delivery reports, bounce handling, and event notifications. See exactly what happens to every email you send. ### White-Glove Support Direct access to delivery experts. Custom implementation assistance, proactive account monitoring, and deliverability consulting. Use Cases ## What Can You Send With OutboundSMTP? OutboundSMTP handles the email infrastructure so your team can focus on what they do best. ### Transactional Email Order confirmations, password resets, receipts ### Application Alerts System notifications, monitoring alerts, logs ### Marketing Campaigns Newsletters, promotions, drip sequences ### Tenant Migrations Queuing during Office 365 / Google migrations #### Delivery Dashboard Last 24 hours 47,291 Delivered 99.4% Inbox Rate 0.3% Bounce Rate 12AM 12PM Now 99.9% Uptime SLA <1s Delivery Time 24/7 Expert Support SOC 2 Compliant Enterprise Ready ## What Security Standards Does OutboundSMTP Meet? SOC 2 Type II Certified TLS 1.2+ Encrypted Transit GDPR EU Compliant HIPAA BAA Available DKIM Auto-Signing SPF Managed Records DMARC Full Alignment PCI DSS Compliant The DuoCircle Ecosystem ## What Else Do You Need for Email Deliverability? Reliable email delivery requires great infrastructure, proper authentication, inbox placement monitoring, and continuous optimization. OutboundSMTP is one piece of a complete ecosystem. [ You are here OutboundSMTP SMTP relay with dedicated IPs, sub-accounts, and white-glove support. ](/)[ Authentication DMARC Report AI-powered DMARC analysis, aggregate & forensic reporting, multi-domain monitoring. ](https://dmarcreport.com)[ Authentication AutoSPF Automatic SPF flattening so you never hit the 10-lookup limit. ](https://autospf.com)[ Coming Soon Inbox Issue Inbox placement testing and deliverability intelligence. Know where your emails actually land. ](#) All products by [DuoCircle](https://www.duocircle.com/) — email security and infrastructure since 2008. ## Ready to start sending? Get 1,000 free email credits. No credit card required. [Start Free Trial→](https://insight.iljmp.com/4/smtp-free)[View Pricing](/pricing/) Frequently Asked Questions ## Common questions about OutboundSMTP ### What is OutboundSMTP? OutboundSMTP is an enterprise SMTP relay service built for complex email requirements. Unlike high-volume-only providers, we specialize in dedicated IP addresses, advanced authentication, sub-account management, and white-glove support for businesses that need reliable, authenticated email delivery. ### What is the difference between a dedicated IP and a shared IP? A dedicated IP gives you full control over your sending reputation, since only your emails are sent from that address. Shared IPs pool traffic from multiple senders, meaning another sender's bad practices can hurt your deliverability. OutboundSMTP includes dedicated IPs with IP warming assistance and custom PTR records on Professional and Enterprise plans. ### How does OutboundSMTP handle email authentication (SPF, DKIM, DMARC)? OutboundSMTP fully manages email authentication for you. We provide automatic DKIM signing, SPF record management, and DMARC alignment support. You can also configure custom MAIL FROM domains for complete control over your authentication chain, helping your emails pass strict inbox filtering policies. ### How much does OutboundSMTP cost? OutboundSMTP offers four plans: Free (1,000 email credits at no cost), Starter at $4/month for low-volume senders, Professional at $14/month with dedicated IPs and advanced features, and Enterprise starting at $69/month for high-volume and regulated industries with custom configurations and priority support. ### How long does it take to set up OutboundSMTP? Most customers are sending email within minutes. Point your application to smtp.outboundsmtp.com on port 587, authenticate with your API key, and you are ready to go. For dedicated IP setups, our delivery experts provide hands-on warming assistance to build your sending reputation quickly and safely. ### What kind of support does OutboundSMTP provide? OutboundSMTP provides 24/7 expert support from real email delivery specialists, not chatbots. Enterprise customers get white-glove onboarding, proactive account monitoring, deliverability consulting, and custom implementation assistance. All plans include access to our support team for technical questions and troubleshooting. ```json {"@context":"https://schema.org","@type":"Organization","name":"OutboundSMTP","url":"https://outboundsmtp.com","logo":{"@type":"ImageObject","url":"https://outboundsmtp.com/images/outboundsmtp-logo.png"},"description":"Enterprise SMTP relay service by DuoCircle. Dedicated IPs, sub-accounts, full authentication, and reliable email delivery for businesses of all sizes.","parentOrganization":{"@type":"Organization","@id":"https://www.wikidata.org/wiki/Q138883901","name":"DuoCircle LLC","url":"https://www.duocircle.com","sameAs":["https://www.wikidata.org/wiki/Q138883901","https://www.crunchbase.com/organization/duocircle-llc","https://www.linkedin.com/company/duocircle","https://github.com/duocircle"],"subOrganization":[{"@type":"Organization","@id":"https://www.wikidata.org/wiki/Q138898167","name":"DMARC Report","url":"https://dmarcreport.com"},{"@type":"Organization","@id":"https://www.wikidata.org/wiki/Q138897474","name":"AutoSPF","url":"https://autospf.com"},{"@type":"Organization","@id":"https://www.wikidata.org/wiki/Q138897912","name":"Phish Protection","url":"https://www.phishprotection.com"}]},"sameAs":["https://www.linkedin.com/company/duocircle","https://www.facebook.com/duocircle/","https://x.com/duocircle","https://github.com/duocircle"],"aggregateRating":{"@type":"AggregateRating","ratingValue":"4.7","reviewCount":"15","bestRating":"5","worstRating":"1","url":"https://www.g2.com/products/outbound-smtp/reviews"},"contactPoint":{"@type":"ContactPoint","contactType":"customer support","url":"https://outboundsmtp.com/contact-us/"},"knowsAbout":["SMTP Relay","Email Delivery","Email Infrastructure","Dedicated IP Addresses","Email Authentication","SPF","DKIM","DMARC","Transactional Email","Outbound Email"]} ``` ```json {"@context":"https://schema.org","@type":"WebSite","name":"OutboundSMTP","url":"https://outboundsmtp.com","description":"Enterprise SMTP relay service by DuoCircle. Dedicated IPs, sub-accounts, full authentication, and reliable email delivery for businesses of all sizes.","publisher":{"@type":"Organization","name":"OutboundSMTP","url":"https://outboundsmtp.com","logo":{"@type":"ImageObject","url":"https://outboundsmtp.com/images/outboundsmtp-logo.png"},"description":"Enterprise SMTP relay service by DuoCircle. Dedicated IPs, sub-accounts, full authentication, and reliable email delivery for businesses of all sizes.","parentOrganization":{"@type":"Organization","@id":"https://www.wikidata.org/wiki/Q138883901","name":"DuoCircle LLC","url":"https://www.duocircle.com","sameAs":["https://www.wikidata.org/wiki/Q138883901","https://www.crunchbase.com/organization/duocircle-llc","https://www.linkedin.com/company/duocircle","https://github.com/duocircle"],"subOrganization":[{"@type":"Organization","@id":"https://www.wikidata.org/wiki/Q138898167","name":"DMARC Report","url":"https://dmarcreport.com"},{"@type":"Organization","@id":"https://www.wikidata.org/wiki/Q138897474","name":"AutoSPF","url":"https://autospf.com"},{"@type":"Organization","@id":"https://www.wikidata.org/wiki/Q138897912","name":"Phish Protection","url":"https://www.phishprotection.com"}]}}} ``` ```json {"@context":"https://schema.org","@type":"SoftwareApplication","name":"OutboundSMTP","url":"https://outboundsmtp.com","applicationCategory":"WebApplication","operatingSystem":"Web","description":"Enterprise SMTP relay service for complex email requirements. Dedicated IPs, advanced authentication, white-glove support, and specialized solutions for high-volume and regulated industries.","provider":{"@type":"Organization","name":"OutboundSMTP","url":"https://outboundsmtp.com","logo":{"@type":"ImageObject","url":"https://outboundsmtp.com/images/outboundsmtp-logo.png"},"description":"Enterprise SMTP relay service by DuoCircle. Dedicated IPs, sub-accounts, full authentication, and reliable email delivery for businesses of all sizes.","parentOrganization":{"@type":"Organization","@id":"https://www.wikidata.org/wiki/Q138883901","name":"DuoCircle LLC","url":"https://www.duocircle.com","sameAs":["https://www.wikidata.org/wiki/Q138883901","https://www.crunchbase.com/organization/duocircle-llc","https://www.linkedin.com/company/duocircle","https://github.com/duocircle"],"subOrganization":[{"@type":"Organization","@id":"https://www.wikidata.org/wiki/Q138898167","name":"DMARC Report","url":"https://dmarcreport.com"},{"@type":"Organization","@id":"https://www.wikidata.org/wiki/Q138897474","name":"AutoSPF","url":"https://autospf.com"},{"@type":"Organization","@id":"https://www.wikidata.org/wiki/Q138897912","name":"Phish Protection","url":"https://www.phishprotection.com"}]}},"offers":{"@type":"AggregateOffer","priceCurrency":"USD","lowPrice":"0","highPrice":"69","offerCount":4,"offers":[{"@type":"Offer","name":"Free","price":"0","priceCurrency":"USD","availability":"https://schema.org/InStock"},{"@type":"Offer","name":"Starter","price":"4","priceCurrency":"USD","availability":"https://schema.org/InStock"},{"@type":"Offer","name":"Professional","price":"14","priceCurrency":"USD","availability":"https://schema.org/InStock"},{"@type":"Offer","name":"Enterprise","price":"69","priceCurrency":"USD","availability":"https://schema.org/InStock"}]}} ``` ```json {"@context":"https://schema.org","@type":"FAQPage","mainEntity":[{"@type":"Question","name":"What is OutboundSMTP?","acceptedAnswer":{"@type":"Answer","text":"OutboundSMTP is an enterprise SMTP relay service built for complex email requirements. Unlike high-volume-only providers, we specialize in dedicated IP addresses, advanced authentication, sub-account management, and white-glove support for businesses that need reliable, authenticated email delivery."}},{"@type":"Question","name":"What is the difference between a dedicated IP and a shared IP?","acceptedAnswer":{"@type":"Answer","text":"A dedicated IP gives you full control over your sending reputation, since only your emails are sent from that address. Shared IPs pool traffic from multiple senders, meaning another sender's bad practices can hurt your deliverability. OutboundSMTP includes dedicated IPs with IP warming assistance and custom PTR records on Professional and Enterprise plans."}},{"@type":"Question","name":"How does OutboundSMTP handle email authentication (SPF, DKIM, DMARC)?","acceptedAnswer":{"@type":"Answer","text":"OutboundSMTP fully manages email authentication for you. We provide automatic DKIM signing, SPF record management, and DMARC alignment support. You can also configure custom MAIL FROM domains for complete control over your authentication chain, helping your emails pass strict inbox filtering policies."}},{"@type":"Question","name":"How much does OutboundSMTP cost?","acceptedAnswer":{"@type":"Answer","text":"OutboundSMTP offers four plans: Free (1,000 email credits at no cost), Starter at $4/month for low-volume senders, Professional at $14/month with dedicated IPs and advanced features, and Enterprise starting at $69/month for high-volume and regulated industries with custom configurations and priority support."}},{"@type":"Question","name":"How long does it take to set up OutboundSMTP?","acceptedAnswer":{"@type":"Answer","text":"Most customers are sending email within minutes. Point your application to smtp.outboundsmtp.com on port 587, authenticate with your API key, and you are ready to go. For dedicated IP setups, our delivery experts provide hands-on warming assistance to build your sending reputation quickly and safely."}},{"@type":"Question","name":"What kind of support does OutboundSMTP provide?","acceptedAnswer":{"@type":"Answer","text":"OutboundSMTP provides 24/7 expert support from real email delivery specialists, not chatbots. Enterprise customers get white-glove onboarding, proactive account monitoring, deliverability consulting, and custom implementation assistance. All plans include access to our support team for technical questions and troubleshooting."}}]} ```