Abstract: A hydrogen fuel coupling system may include a hydrogen fuel tank and a hydrogen fuel supply connector. The tank has a first connector, and a second connector disposed around the first connector. The second connector has a boil-off inlet port for receiving gaseous hydrogen from the tank. The hydrogen fuel supply connector may include a hydrogen fuel transfer line, a third connector for operably sealably connecting the transfer line to a first connector of the tank for supplying liquid hydrogen, and a shroud extending around the third connector and the transfer line defining a gap therebetween. A fourth connector operably sealably connects a first end of the shroud to a second connector of the tank. A second end of the shroud is operably sealably engageable with the transfer line. A boil-off vent is connected to the shroud for venting gas from the gap.