{"id":7948,"date":"2026-10-24T12:51:49","date_gmt":"2026-10-24T05:51:49","guid":{"rendered":"https:\/\/adtek.agency\/glossary\/email-marketing\/"},"modified":"2026-10-24T13:16:05","modified_gmt":"2026-10-24T06:16:05","slug":"email-marketing","status":"publish","type":"mona_glossary","link":"https:\/\/adtek.agency\/en\/glossary\/email-marketing\/","title":{"rendered":"Email marketing"},"content":{"rendered":"<p>Email marketing is a business sending emails to people who agreed to receive them, to introduce products, look after customers or bring them back to buy again. An email list is a channel the business owns, so there is no per-impression cost like there is with ads.<\/p>\n<h2>What is email marketing?<\/h2>\n<p>An email marketing program needs a recipient list, content and sending software (an ESP, or email service provider) that tracks open rates, click rates and unsubscribes. Common types of email:<\/p>\n<ul>\n<li>Newsletters sent on a regular schedule.<\/li>\n<li>Promotional emails for each sale.<\/li>\n<li>Automated sequences: welcoming new subscribers, reminding people about abandoned carts, inviting past buyers back. This part falls under <a href=\"https:\/\/adtek.agency\/en\/glossary\/marketing-automation\/\">marketing automation<\/a>.<\/li>\n<\/ul>\n<p>Build the list yourself through sign-up forms, member accounts and orders, and keep it alongside purchase history in your <a href=\"https:\/\/adtek.agency\/en\/glossary\/crm\/\">CRM<\/a>.<\/p>\n<h2>Rules for promotional email in Vietnam<\/h2>\n<p>Decree 91\/2020\/ND-CP on combating spam messages, spam emails and spam calls took effect on October 1, 2020. A promotional email sent without the recipient&#8217;s prior consent counts as spam (Article 3). The main provisions (<a href=\"https:\/\/datafiles.chinhphu.vn\/cpp\/files\/vbpq\/2020\/08\/91.signed.pdf\" target=\"_blank\" rel=\"nofollow noopener\">Decree 91\/2020\/ND-CP, Vietnam Government Portal, August 2020<\/a>):<\/p>\n<ul>\n<li>Send only to people who consented in advance, for example through a sign-up form on a website, app or social network. Records of sign-ups and refusals must be kept for at least 1 year (Article 11).<\/li>\n<li>No more than 3 promotional emails to one email address within 24 hours, unless you have a different agreement with the recipient (Article 13).<\/li>\n<li>Put the label [QC] or [AD] at the very start of the subject line (Article 18).<\/li>\n<li>Show the advertiser&#8217;s name, phone number, email and address directly above the opt-out section (Article 19).<\/li>\n<li>Place the opt-out section at the end of the email, and let people opt out via a website or social network, by email and by phone. When a request arrives, send a confirmation right away and stop sending (Article 20).<\/li>\n<\/ul>\n<p>A customer&#8217;s email address is personal data, so Vietnam&#8217;s Personal Data Protection Law No. 91\/2025\/QH15 also applies (see our guide to <a href=\"https:\/\/adtek.agency\/en\/vietnam-personal-data-protection-law-marketing\/\">Vietnam&#8217;s personal data protection law for marketers<\/a>).<\/p>\n<h2>Gmail and Yahoo rules for bulk senders<\/h2>\n<p>Since February 1, 2024, anyone sending more than 5,000 emails a day to personal Gmail accounts must authenticate their domain with SPF, DKIM and DMARC and keep the spam rate reported in Postmaster Tools below 0.3%. Marketing emails must support one-click unsubscribe and include a clearly visible unsubscribe link in the body (<a href=\"https:\/\/support.google.com\/a\/answer\/81126?hl=en\" target=\"_blank\" rel=\"nofollow noopener\">Google, Email sender guidelines, accessed October 2026<\/a>).<\/p>\n<p>The 5,000 threshold counts all mail sent from the same primary domain. Google recommends handling unsubscribe requests within 48 hours (<a href=\"https:\/\/support.google.com\/a\/answer\/14229414?hl=en\" target=\"_blank\" rel=\"nofollow noopener\">Google, Email sender guidelines FAQ, accessed October 2026<\/a>). Yahoo has similar requirements and states that unsubscribes should be honored within 2 days (<a href=\"https:\/\/senders.yahooinc.com\/best-practices\/\" target=\"_blank\" rel=\"nofollow noopener\">Yahoo Sender Hub, Best practices, accessed October 2026<\/a>).<\/p>\n<h2>Illustrative example (hypothetical)<\/h2>\n<p>A fashion shop has 10,000 subscribers. Each sale newsletter gets 2% of recipients to click through to the site (200 people), and 5% of those buy (10 orders) at an average of VND 500,000. Each send brings in 10 x 500,000 = VND 5 million, so 4 newsletters a month bring in VND 20 million against VND 1.5 million in software costs.<\/p>\n<h2>Email marketing vs transactional email vs spam<\/h2>\n<table>\n<tr>\n<th>Type<\/th>\n<th>Purpose<\/th>\n<th>Example<\/th>\n<\/tr>\n<tr>\n<td>Email marketing<\/td>\n<td>Introduce products and promotions to people who opted in<\/td>\n<td>An 11.11 sale newsletter<\/td>\n<\/tr>\n<tr>\n<td>Transactional email<\/td>\n<td>Notify customers about something they just did<\/td>\n<td>Order confirmation, password reset<\/td>\n<\/tr>\n<tr>\n<td>Spam email<\/td>\n<td>Promotional email sent without consent or against the rules<\/td>\n<td>Mailing a purchased email list<\/td>\n<\/tr>\n<\/table>\n<p>To message customers on Zalo (a Vietnamese messaging app) instead of email, see <a href=\"https:\/\/adtek.agency\/en\/glossary\/zalo-notification-service-zns\/\">ZNS (Zalo Notification Service)<\/a>.<\/p>\n<h2>Frequently asked questions<\/h2>\n<h3>Can I buy an email list and send to it?<\/h3>\n<p>You shouldn&#8217;t. Decree 91\/2020 requires advertisers to be able to verify each recipient&#8217;s prior consent. Purchased lists almost never come with that proof.<\/p>\n<h3>Do emails to past customers need the [QC] label?<\/h3>\n<p>An email that introduces products or promotions is a promotional email under Article 3, so it still needs the label even if the recipient has bought from you before.<\/p>\n<p>If you need to set up email capture from ads and measure all the way to orders, see Adtek&#8217;s <a href=\"https:\/\/adtek.agency\/en\/solution\/lead-generation\/\">Lead Generation<\/a> page.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Email marketing is a business sending emails to people who agreed to receive them, to introduce products, look after customers or bring them back to buy again. An email list is a channel the business owns, so there is no per-impression cost like there is with ads. What is email marketing? An email marketing program [&hellip;]<\/p>\n","protected":false},"author":4,"featured_media":0,"comment_status":"open","ping_status":"closed","template":"","meta":{"_acf_changed":false,"_yoast_wpseo_title":"Email Marketing: What It Is and Vietnam Email Rules","_yoast_wpseo_metadesc":"What is email marketing? 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