When you move, regardless of whether you move interstate or intrastate, the ATF wants you to update them regarding the permanent location where your NFA firearms will be stored. The ATF’s change of address form is ATF Form 5320.20, entitled “Application to Transport Interstate or to Temporarily Export Certain National Firearms (NFA) Firearms. If you are moving intrastate (within the same state), you can file the change of address form after you move. However, if you are moving interstate (across state lines), you need a be a little more careful. If the only NFA firearms that your gun trust owns are silencers, you can file your change of address form after you move. However, for any other type of NFA firearm, such as a short-barreled rifle (“SBR”), short-barreled shotgun (“SBS”), fully-automatic weapon (“machinegun”), etc., you must file your change of address form with the ATF before you move. After you receive the approved change of address form back from the ATF in the mail, then you can move these types of NFA firearms across state lines.