From Mailchimp to Postal, without reactivating people who left the list

Before exporting, agree on who does what. Don't close Mailchimp yet: you'll need it until the end.

• Whoever exports must be an Owner or Admin of the Mailchimp account.
• Create your Postal account. See your plan's contact limit on Pricing: the Free plan has 1,000 contacts, Pro 5,000 and Scale 50,000.
• Make a list of what exists in Mailchimp: audiences, groups, tags, saved segments, templates, campaigns, automations and forms.
• If you have more than one audience, remember that in Postal each email is a single contact per team. Merge what makes sense and use segments to separate them.
• Whoever manages your site or domain will need to publish a few DNS records (next step).

For Postal to send on behalf of your brand, the domain must be verified. In Domains, Postal shows a few records for whoever manages DNS to copy, and checks them on its own for up to 72 hours, flagging what's wrong.

• Prefer a subdomain just for marketing, like news.exemplo.com.br. That way, whatever happens with your campaigns does not affect your system's emails.
• Check whether any existing record has the same name before you publish the new ones.
• Names are relative to the domain. If your DNS panel complains about a repeated domain, remove it from the name. The details are in Domains and DNS.

In Mailchimp, open Audience, click Export audience, then Export CSV. The file may arrive as a ZIP with one CSV for each type of contact.

• The file includes the audience fields, tags (TAGS), the date and IP of the signup (OPTIN_TIME and OPTIN_IP) and those of the confirmation (CONFIRM_TIME and CONFIRM_IP).
• According to Mailchimp, the file does not include: opens and clicks, purchases, language and signup source.
• You can also export just one segment, tag or group with Export segment.
• The file stays available in your account for 30 days.
• If accents look wrong in Excel, do not save over the file: Postal reads files in UTF-8 and Windows-1252.

Mailchimp splits contacts into four statuses, and each one goes to a different place in Postal. This is where you protect the people who asked to leave.

• Unsubscribed: in their file, leave an Unsubscribed column filled with sim in every row and map that column to the Unsubscribed (yes/no) field in the import.
• Subscribed: do not map the Unsubscribed column. For people already in Postal, the value in the file wins: a “no” would reactivate someone who already left.
• Cleaned: during import, Postal ignores addresses that are on the suppression list. To suppress a large list, use the API (POST /suppressions/batch/add, 100 at a time) with help from whoever looks after your system; in the dashboard, Suppressions accepts one address at a time. Without the API, import the cleaned contacts along with the unsubscribed ones: they will never receive campaigns, but they take up a spot in your plan's contact limit.
• Non-subscribed: the safe default is to leave them out. If you have another legal basis for contacting them, the decision is yours and it must be documented.

In Audience, on the Contacts tab, click Import CSV. Choose the file, say which field each column matches and check the preview before importing. The import runs in the background and you can follow the result.

• First create the Properties for the custom fields you want to keep, such as city or date of last purchase. The types are text, number, yes/no and date.
• The tags column accepts names separated by commas or semicolons. Any that do not exist are created.
• Mailchimp groups can become Topics. The simplest way is to export each group as a segment and import each file, selecting the topic in Subscribe to topics. That field subscribes every contact in the file.
• Leave the Trigger automations option off. When it is on, each new contact can start automations, and a large list may receive the welcome sequence all at once.
• Contacts that already exist are updated by email. Empty cells do not erase values, and repeated emails in the file count only the first time. Rows with errors appear in the result.
• Each file can be up to 20 MB: split larger ones. The import stops when your plan's contact limit is reached.
• Keep the consent record: create properties such as origem and data_inscricao and import the signup date and IP into them. The date type stores only the day.
• Before sending, run the list through Email validation, which flags invalid and risky addresses.

Templates and campaigns do not carry over on their own. What you can take with you is the HTML, and the rest has to be rebuilt.

• Templates coded in Mailchimp: in Campaigns > Email templates, open More options and choose Export as template to download the HTML. According to Mailchimp, drag-and-drop editor templates cannot be exported this way.
• The full account export brings a folder with the HTML of templates and campaign emails. Only one is allowed per 24 hours and it can take up to 24 hours. Check what came through, because Mailchimp does not detail the case of drag-and-drop templates.
• In Postal, under Templates, build the email in the visual editor or paste the HTML. Campaigns also accept HTML. If the HTML points to Mailchimp images, upload the images again before closing your account.
• To rebuild a campaign, open Campaigns and choose the segment (and, if you want, the topic), the sender from a verified domain, the subject and the preview text. Send a test and schedule it.
• Who receives it: only contacts in the segment who are not unsubscribed, not on the suppression list and, if there is a topic, subscribed to it.
• Campaigns already sent are not imported. Keep the HTML and the reports: in Mailchimp, View analytics > Download All Reports generates an export of campaign reports (automations are left out, and the file does not show who opened or clicked). Postal keeps emails, events and logs for 30 days.

Mailchimp's documentation only describes copying an automation within the same account. We did not find an export to another platform, so treat each flow as new and use the chance to review what still makes sense.

• The available steps are wait, send email, check a condition, change the contact and call a webhook. A/B testing depends on the plan.
• Imports don't start automations unless you turn that option on. Review who would enter before you activate it.
• Each plan has a monthly limit of runs. See Automations.

Hosted, embedded and pop-up forms keep sending people to Mailchimp for as long as they stay live. Recreate each one in Postal and swap the address or the code on your site.

• Under Forms, use the ready-made page (forms.postal.so/seu-nome) or submit from your own site.
• Turn on double opt-in: the person confirms their email before joining the audience.
• A consent field stores the date and IP of the opt-in. Each answer can be saved to a property, subscribe the person to topics and add them to a segment.
• Only turn off the Mailchimp form after the new one is live and tested. See Forms.

Before the first campaign, look over this table and the consent checklist. It applies to any list you bring from another platform.

• Also read Email marketing: best practices and unsubscribing.