The Merarites, according to their families, were allotted twelve cities from the tribes of Reuben, Gad, and Zebulun.

Joshua 21:7
And the descendants of Merari received twelve cities from the tribes of Reuben, Gad, and Zebulun.

Joshua 21:34
This is what the Merarite clan (the rest of the Levites) were given: From the tribe of Zebulun they were given Jokneam, Kartah,

1 Chronicles 6:62
The Gershomites, according to their clans, were allotted thirteen cities from the tribes of Issachar, Asher, Naphtali, and Manasseh in Bashan.

To the sons of Merari were given by lot, throughout their families, out of the tribe of Reuben, and out of the tribe of Gad, and out of the tribe of Zebulun, twelve cities.