What do I need to do to opt for the NCOA feature? All mailers sent through Lob will get run through NCOA as part of our production workflow. Related articles Can I run a NCOA check for international addresses? What is National Change of Address (“NCOA”)? Can I use custom fonts in HTML? What are Priority Mail Queuing and Lob’s Service Level Guarantee? What do the different US Mail Strictness Settings do?