FTP and RETS are the two types of data feeds for third-party vendors, such as IDX Broker, to use to aggregate MLS data and display it on approved real estate websites.
FTP stands for File Transfer Protocol. This is an older method of moving files around. FTP is tried and true, but has its limitations. With FTP, the entire file has to be moved all at once. MLS/IDX data we receive via FTP is typically of decent quality, but can lack a lot of fields. Generally speaking, FTP provided data from your MLS is going to be fairly simple data.
RETS stands for Real Estate Transaction Standard. RETS is a relatively new means of requesting and receiving data, specific to the Real Estate industry. In most cases, we are able to connect to your MLS’s RETS server, request certain data, and that request is then available for us as a download. What’s nice about RETS, is that we can get pieces of data, rather than a giant file. Also, it is possible get pieces, or chunks of data at many different times of the day. Also, because there are fewer limitations on data accessed via RETS, the data tends to be far more robust when compared to data received via FTP.
The primary difference between FTP and RETS, from a REALTOR perspective, is that the RETS data is designed to match each MLS's unique practices so it typically resembles the field names and option values more closely to what you see when logged in to the MLS itself. RETS is also easier for third-party vendors to troubleshoot than a FTP feed, so any issues can usually be diagnosed and corrected quickly. Overall, RETS is more robust, typically contains more fields, is easier to access and is easier to support.
Which should you use?
In some cases, your MLS might offer data access in both manners. If this is the case, we always recommend that you choose RETS as the method for which we access and receive data for you. However, we do realize that some MLS’s have different fees for you to get approved for the different data resources. If this is the case, please consider RETS, even though it might have higher costs associated with your approval and/or data license.