--- title: "SMTP Relay Service: the mailman you didn't know you needed" description: The SMTP Relay Service is like a personal mailman (or a bodyguard even) who ensures all your emails arrive securely and swiftly at their destination. image: https://www.smartlockr.io/hubfs/smtp-smarlockr%20(1).webp --- [![Smartlockr logo](https://www.smartlockr.io/hubfs/Smartlockr-logo.png) ](https://www.smartlockr.io/en?hsLang=en) - Product - [Product overview ](https://www.smartlockr.io/en/product?hsLang=en) - [Integrations ](https://www.smartlockr.io/en/integrations?hsLang=en) - Customers - [Case studies ](https://www.smartlockr.io/en/blog/tag/casestudy) - Team - [Management ](https://www.smartlockr.io/en/teams/management?hsLang=en) - [IT specialist ](https://www.smartlockr.io/en/teams/it-specialist?hsLang=en) - [CISO ](https://www.smartlockr.io/en/teams/ciso?hsLang=en) - [End user ](https://www.smartlockr.io/en/teams/end-user?hsLang=en) - Branches - [Healthcare ](https://www.smartlockr.io/en/branches/secure-email-healthcare?hsLang=en) - [Municipalities ](https://www.smartlockr.io/en/branches/secure-email-municipalities?hsLang=en) - [Finance ](https://www.smartlockr.io/en/branches/secure-email-financial-services?hsLang=en) - [Legal ](https://www.smartlockr.io/en/branches/secure-email-legal-industry?hsLang=en) - [Education ](https://www.smartlockr.io/en/branches/secure-email-education?hsLang=en) - [Recruitment ](https://www.smartlockr.io/en/branches/secure-email-recruiters?hsLang=en) - [Housing associations ](https://www.smartlockr.io/en/branches/secure-email-housing-associations?hsLang=en) - [Pricing ](https://www.smartlockr.io/en/pricing?hsLang=en) - Resources - [Blog ](https://www.smartlockr.io/en/blog) - [Guides ](https://www.smartlockr.io/en/resources?hsLang=en#guides) - [Webinars ](https://www.smartlockr.io/en/resources?hsLang=en#webinars) - [Videos ](https://www.smartlockr.io/en/resources?hsLang=en#videos) - [Partners ](https://www.smartlockr.io/en/partners?hsLang=en) - Company - [Contact ](https://www.smartlockr.io/en/contact?hsLang=en) - [Support ](https://support.smartlockr.io/hc/en-us?hsLang=en) - [Request more licenses ](https://www.smartlockr.io/en/request-more-licenses?hsLang=en) - [Who we are ](https://www.smartlockr.io/en/about-us?hsLang=en) - [Jobs ](https://www.smartlockr.io/en/careers?hsLang=en) [![Free Consultation](https://no-cache.hubspot.com/cta/default/6122972/846d7346-3e53-4811-b976-8a3dd0a3f9ee.png)](https://cta-redirect.hubspot.com/cta/redirect/6122972/846d7346-3e53-4811-b976-8a3dd0a3f9ee) # SMTP Relay Service: the mailman you didn't know you needed [ Smartlockr ](https://www.smartlockr.io/en/blog/author/smartlockr) Oct 29, 2021 --- ![SMTP Relay Service: the mailman you didn't know you needed](https://www.smartlockr.io/hubfs/smtp-smarlockr%20(1).webp) Question: what happens to your data after you click on ‘Send’? When you mail a letter the old fashioned way, you’d expect it to arrive at its intended destination in a matter of days. Considering everything that needs to happen for your letter to get from A to B, this is actually quite an impressive feat. Even more so in the case of emails. The real question is: who’s the mailman for your emails? Make secure communication easy by [scheduling your demo](https://www.smartlockr.io/en/request-demo?hsLang=en) today with one of our data security experts!   ## The more you email, the more important your process Does your organisation regularly send out emails with confidential information, bulks of automated invoices, or perhaps marketing emails to large groups of customers? The more emails you send, the more essential it is to streamline this effort. For one thing, every major email provider warrants against spamming. Sending one email to a colleague? No problem. 1000 automated messages per day? That’s another story. Your email provider will play it safe and prevent your email from arriving at its destination or, even worse, have it end up at unauthorised parties. Most importantly though, you’ll want to make sure every email you send it secured. If preventing data breaches is important to you that is. Of course Smartlockr makes it very easy to secure each and every email you send with the click of a button, but the more emails you send, the more clicks you’ll need to ensure your data stays safe.   ## Increase security and efficiency simultaneously The solution: a mailman, but slightly upgraded: [Smartlockr’s SMTP Relay Service](https://www.smartlockr.io/en/smtp-relay-service?hsLang=en) (“Simple Mail Transfer Protocol”, in case you ever get that question at a trivia quiz) is the mailman you didn’t know you needed. Smartlockr’s SMTP Relay Service has a simple purpose: it ensure all your emails are sent with the right security and end up at the intended recipient. To illustrate: sending emails without an SMTP Relay Service is like expecting a carrier pigeon to flawlessly deliver thousands of letters at exactly the right destination. Not something you’d do lightly. Sending emails using the Smartlockr SMTP Relay Service is akin to giving thousands of letters to an equal amount of personal bodyguards who’ll protect your data with their lives and make sure your data arrives at its right destination. To sum up the benefits of the Smartlockr SMTP Relay Service: 1. Everyone in your organisation emails **100% securely**, without any effort whatsoever. 2. Everyone works in **their own familiar environment**, like Outlook (in a browser), Gmail or on a mobile phone. All without the need for separate apps that impose on existing work processes (read: 'separate apps that increase the odds of a data breach happening). 3. Does your organisation use a content filter? The Smartlockr SMTP Relay Service **jumps into action** the moment an email and/or attachment contains any sensitive data. 4. Have you ***whitelisted* **one or more email domains? No problem, Smartlockr will immediately, saving you precious time. Of course, *blacklisted* email domains will automatically be blocked forward your emails to those domains. 5. Last but not least: it makes **life a lot easier** if you’re an IT professional. You’ll spend way less time being a help desk, leaving you with more time to do actual IT work.   ## Experience it for yourself! Comparing the Smartlockr SMTP Relay Service with a mailman doesn’t do the first one justice. It’s a bit like comparing a bike to a Ferrari. Do you want to experience the difference between a bike and a Ferrari, or would you settle for everyone in your organisation being able to email 100% securely with 0% effort? Click on the link below to schedule a free demo from one of our data security experts! [![Probeer nu vrijblijvend](https://no-cache.hubspot.com/cta/default/6122972/52b43707-908b-4865-b6f1-01acc88d92d2.png)](https://cta-redirect.hubspot.com/cta/redirect/6122972/52b43707-908b-4865-b6f1-01acc88d92d2) [Veilig Mailen](https://www.smartlockr.io/en/blog/tag/veilig-mailen) [Feature Friday](https://www.smartlockr.io/en/blog/tag/feature-friday) [![secure communication](https://www.smartlockr.io/hs-fs/hubfs/secure-communication-bp.png?width=336&name=secure-communication-bp.png)](https://www.smartlockr.eu/en/request-demo?hsLang=en)   ### Whitepapers - [Is it safe to store data in a US-based Cloud provider?](https://www.smartlockr.eu/en/whitepaper-is-it-safe-store-data-us-cloud-provider?hsLang=en) - [Good cop, bot cop: the truth about AI, ML and your privacy](https://www.smartlockr.eu/en/whitepaper-ai-ml-and-data-privacy?hsLang=en) - [The 8 things you can expect from a partnership with Smartlockr](https://www.smartlockr.eu/en/whitepaper-things-you-can-expect-from-partnetship-smartlockr?hsLang=en) - [How to choose the right secure email solution?](https://www.smartlockr.eu/en/how-to-choose-the-right-secure-email-solution-whitepaper?hsLang=en) - [Keep your organization free of data leaks](https://www.smartlockr.eu/en/keep-organization-free-of-data-leaks?hsLang=en) - [Smartlockr & Workspace 365: Prevent data breaches, work and communicate more securely](https://www.smartlockr.eu/en/safe-emailing-and-safe-workplace?hsLang=en) ### Popular Post [ Oops, I sent an important email to the wrong recipient. What now? ](https://www.smartlockr.io/en/blog/sent-email-to-wrong-recipient-what-now?hsLang=en) [ Is Microsoft 365 GDPR-compliant? Spoiler alert: no ](https://www.smartlockr.io/en/blog/is-microsoft-365-gdpr-compliant?hsLang=en) [ Recall sent emails to protect data: block emails, files and recipients ](https://www.smartlockr.io/en/blog/recall-sent-email?hsLang=en) [ Why Pentesting is a must for banks and financial services ](https://www.smartlockr.io/en/blog/why-pentesting-is-a-must-for-banks-and-financial-services?hsLang=en) [ Preventing misdirected emails with files and recipients confirmation ](https://www.smartlockr.io/en/blog/confirmation-on-files-and-recipients?hsLang=en) ## Similar posts ### [Protect your data and save time with Smartlockr Document Scanning](https://www.smartlockr.io/en/blog/document-scanning-smartlockr?hsLang=en) Smartlockr Document Scanning enables you to automatically scan your attachments for sensitive information, making email security easier and saving... SmartLockr Oct 14, 2021 ### [Have you tried turning your awareness off and on again?](https://www.smartlockr.io/en/blog/have-you-tried-turning-your-awareness-off-and-on-again?hsLang=en) Awareness: essential part of cyber security. Distraction: essential part of us. Discover an email solution that increases awareness without any effort data protection Jul 14, 2021 [![Smartlockr logo](https://www.smartlockr.io/hubfs/smartlockr-logo2.png) ](https://www.smartlockr.io/nl/?hsLang=en) **Netherlands: **H.J.E Wenckebachweg 123 1096 AM, Amsterdam Kvk: 61781614 BTW-nr: NL854485685B01   ### Contact - Netherlands: +31 (0) 20 244 03 50 - Sweden: +46 81 211 29 68 ### Smartlockr - [Terms & Conditions](https://www.smartlockr.io/en/general-terms-and-conditions-smartlockr?hsLang=en) - [Privacy Statement](https://www.smartlockr.io/en/privacy-statement?hsLang=en) - [Smartlockr A-Z](https://www.smartlockr.io/en/smartlockr-a-z?hsLang=en) - [Status of our services](https://www.smartlockr.io/en/status-of-our-services?hsLang=en) ### Support - [Help Center](https://support.smartlockr.io/hc/en-us?hsLang=en) - [FAQ](https://support.smartlockr.io/hc/en-us/categories/5354862458012-FAQ-and-information?hsLang=en) - [Need help? Download TeamViewer](https://get.teamviewer.com/smartlockr) © 2026 Smartlockr All rights reserved ![BC Certified logo_ISO 27001-2022 RVA_ENG](https://www.smartlockr.io/hs-fs/hubfs/BC%20Certified%20logo_ISO%2027001-2022%20RVA_ENG.jpg?width=303&height=80&name=BC%20Certified%20logo_ISO%2027001-2022%20RVA_ENG.jpg) ![NEN 7510 certificate Smartlockr](https://www.smartlockr.io/hs-fs/hubfs/BC-Certified-logo_NEN7510-1-2017_RVA_ENG.png?width=320&height=85&name=BC-Certified-logo_NEN7510-1-2017_RVA_ENG.png) ```json { "@context" : "https://schema.org", "@type" : "BlogPosting", "author" : { "@type" : "Person", "name" : "Smartlockr", "url" : "https://www.smartlockr.io/en/blog/author/smartlockr" }, "dateModified" : "2023-07-20T15:42:43.859Z", "datePublished" : "2021-10-29T06:43:33.000Z", "headline" : "SMTP Relay Service: the mailman you didn't know you needed", "image" : [ "https://www.smartlockr.io/hubfs/smtp-smarlockr%20(1).webp" ], "mainEntityOfPage" : { "@id" : "https://www.smartlockr.io/en/blog/smtp-relay-service", "@type" : "WebPage" }, "publisher" : { "@type" : "Organization", "logo" : { "@type" : "ImageObject", "url" : "https://www.smartlockr.io/hubfs/SL-logo@3x.png" }, "name" : "Smartlockr" } } ``` ```json { "@context" : "http://schema.org", "@type" : "Organization", "address" : { "@type" : "PostalAddress", "addressCountry" : "", "addressLocality" : "Amsterdam", "addressRegion" : "Noord Holland", "postalCode" : "", "streetAddress" : "H.J.E. Wenckebachweg 123 " }, "alternateName" : "AttachingIT", "areaServed" : { "@type" : "GeoCircle", "geoMidpoint" : { "@type" : "GeoCoordinates", "latitude" : "52.336690", "longitude" : "4.929430" }, "geoRadius" : "150 km" }, "description" : "Secure email and file sharing for businesses that handle privacy sensitive data", "email" : "sales@smartlockr.eu", "image" : "https://www.smartlockr.io/hubfs/homepage-en.png", "logo" : "https://www.smartlockr.io/hubfs/Smartlockr-logo.png", "mainEntityOfPage" : { "@id" : "https://www.smartlockr.io/en/blog/smtp-relay-service", "@type" : "WebPage", "description" : "The SMTP Relay Service is like a personal mailman (or a bodyguard even) who ensures all your emails arrive securely and swiftly at their destination." }, "name" : "Smartlockr", "sameAs" : [ "https://www.linkedin.com/company/smartlockr/", "https://www.youtube.com/@smartlockr9354", "https://www.instagram.com/smartlockr/" ], "telephone" : "+31 (0) 20 244 03 50", "url" : "https://www.smartlockr.io/" } ``` ```json { "@context" : "https://schema.org/", "@type" : "WebSite", "description" : "Secure email and file sharing for businesses that handle privacy sensitive data", "name" : "Smartlockr", "potentialAction" : { "@type" : "SearchAction", "query-input" : "required name=search_term_string", "target" : "https://www.smartlockr.io/hs-search-results{search_term_string}" }, "url" : "https://www.smartlockr.io/" } ```