If you're using Email for Trello to send/receive emails in Trello, you may occasionally receive two different emails concerning the same topic, resulting in two different Trello cards. It can be frustrating and messy to try and correspond separately on the two cards.

Here are a few simple steps you can take to merge two Trello cards into one.

To merge two or more cards, open one of the cards and click on SendBoard > Merge Card. You can then search for the cards to merge and choose what content should be combined on the merged card. Once complete, you’ll end up with a single card that combines all of the comments, attachments and emails.

Here’s an example showing each step of the process.

Make sure you’ve got the Email for Trello Power-Up enabled on your board. Any cards that have an email conversation associated with the card will have a new “Merge Card” option under the SendBoard card menu.

Open one of the cards you’d like to merge and choose “Merge Card” from the SendBoard card menu.

There’s a short wizard that takes you through the options for merging cards.

You'll first need to decide which of the cards is the card you’d like to keep (other cards will be merged into this one). This card might be one that was created first, or it might be the one with the most relevant information. You'll need to decide which makes the most sense for you. But don't stress too much about it, as most information will be merged together anyway.

Once you’ve decided, the next screen allows you to search for the cards to merge with. You’ll only be able to select other cards from the same Trello board. Archived cards will need to be added back to the board before you merge.

The final screen confirms your selection and lets you choose what content to copy across from the merged cards. Emails from both cards will automatically be merged together, but you can optionally choose to copy across comments and card attachments.

Once you finalize the merge process above, you’ll end up with a card that combines all of the emails from the merged cards. Depending on your choices, card comments and attachments will have been copied across to the “card you want to keep” and other cards will be automatically archived.

Opening up the email thread will show the merged email conversation, and if you reply, you’ll be able to optionally include messages from all of the merged cards.

That’s all there is to it.

The Merge Card feature is only available on certain Email for Trello plans.

If you're not using the SendBoard's Email for Trello Power-Up, you won't see the "Merge Card" button. It's not ideal, but there is a workaround you can use to manually connect Trello cards. Trello provides a neat way for two cards to link to each other. By connecting two related Trello cards, you'll ensure information from both cards is easy to find. This won't affect what email messages your contacts will see, but at least you'll have a clear link between the cards in Trello.

To link two cards, open one of the cards and click on Attachment > Trello. You can search here for the other card, or copy the URL for the other card to add it as an attachment. 

Once the attachment is added, you can click 'connect cards' to make the link work both ways. 

You'll need to decide which of the two cards to use as the 'master card'. We'll call the other card the 'duplicate card'. The 'master' might be the earlier of the two cards you created. It might also be the card with the most relevant information on the topic.

Because you are continuing to use the master Trello card only, you'll want to ensure that important content from the duplicate card is copied across. To do this, you'll need to manually copy/paste comments, checklists and other details from one card to another. Remember that the cards are linked, so only copy across important content that you need to show on the master card.

Now that you've merged content into the master card, you can go ahead and archive the duplicate card.