Methods and systems for transmitting data are disclosed. In one example, a method comprises providing, at a publication platform accessible by users via a network, a posting portal to receive entry of data relating to an item for posting on the publication system, the posting portal including an interface having first and second user interface elements to receive the data related to the item for inclusion in the posting. The method includes receiving at least one media file for inclusion in the posting in the first user interface element, and automatically commencing transmission of the at least one media file over the network, for inclusion in the posting, before the user has completed entering information into the second user interface element.