I'm unable to post List through refit. Here's the interface declaration:

[Post("/api/Url/{id}")]
[Headers("Content-Type:application/json")]
Task<Model> PostMethod([Body(BodySerializationMethod.UrlEncoded)] CommandType command)

Here's the CommandType class

public class CommandType
{
    public IEnumerable<Guid> Prop { get; set; }
}

Even though Refit is able to make the call but the argument for Prop is null at the receiving end.

[UPDATE] I tried with [Body(BodySerializationMethod.UrlEncoded)] [Query(CollectionFormat.Multi)] too but no luck!

[FOUND SOLUTION] I've solved it using just the following by removing both Body attribute and CommandType. Instead, put the Property inside the class into the parameter directly. Just FYI.

[Query(CollectionFormat.Multi)] IEnumerable of Guid for Prop