Hi @Maxwell0789 

Good question.

Please reference this help article about specifying the Trello Card position in a List: https://trello.com/c/nbTUHx6s/34-add-a-card-to-any-position-with

Try using the ‘Custom’ option to set the value.

Thank you @Troy Tessalone for the quick reply. 

Unfortunately, it doesn't work with the "custom" field either. I can enter the number 2 (for position 2) but Zapier ignores it when performing. I've tried some special characters in combination with the number, but it doesn't work.

@Maxwell0789

What Trello Zap action are you trying to use?

From the Trello Create Card Zap action, you can specify the Card Position with a number.

This is what is indicated in the Trello API: https://developer.atlassian.com/cloud/trello/rest/api-group-cards/

@Maxwell0789

Figured it out.

Number needs to be a decimal.

e.g. 2.0 for position 2

@Troy Tessalone just found the error.

Trello is using large numbers to specify the position of the card. For example:

First position =85000

Second position =65000

etc…

@Maxwell0789 

That doesn’t seem right.

Did you try using a decimal to specify the position as indicated above?

@Troy Tessalone I tried the decimal numbers first. Wasn't working, so I analyzed  the data from trello and came up with those large numbers for the position. Now it is working. 

Hi @Troy Tessalone and @Maxwell0789 ! I wanted to follow up with this explanation I found in an Atlassian developer community post about the Trello Card Position number: 
 

The pos fields aren’t hashed; they should be numbers. However, they are not whole numbers that increase by 1 for each pos. Instead, the numbers can have a wide range. We do this so that when you insert a new card, or move a card around, we do not have to make an update to every card above the new/moved card.

For instance, if you had three cards in a list with positions 1, 2, and 3. And you decided to insert a new card at the top of the list, making it position 1, you’d also need to update the position fields of all of the other cards in the list.

However, if you had three cards in a list with positions 124, 593, and 1234. And you decided to insert a new card at the top of the list, all you’d need to do is set its position to any value less than 124. No further card position updates required.

 
If you have multiple cards in place already, they will have positions assigned to them, so if you want to place a card between existing cards, ideally you need to know the other cards' positions so that you can choose an appropriate number in-between.