WHO IS A RESIDENT?
You are a resident of Maryland if: a. Your permanent home is or was in Maryland (the law refers to this as your domicile). OR b. Your permanent home is outside of Maryland, but you maintained a place of abode (a place to live) in Maryland for more than six months of the tax year. If this applies to you and you were physically present in the state for 183 days or more, you must file a full-year resident return.
PART-YEAR RESIDENTS
If you began or ended residence in Maryland during the tax year, you must file a Maryland resident income tax return.
MILITARY AND OTHERS WORKING OUTSIDE OF MARYLAND
Military and other individuals whose domicile is in Maryland, but who are stationed or work outside of Maryland, including overseas, retain their Maryland legal residence. Maryland residence is not lost because of duty assignments outside of the State; see Administrative Release 37. Military personnel and their spouses should see Instruction 29.