Proof of Residency
A number of circumstances must be taken into account when determining residency for tax purposes. The taxpayer's main residence is typically defined as the place lived in for over six months during the tax year. Other factors include the place of voter registration, driver's license and car registration, and address of record for bank accounts and school districts.
Some taxpayers spend extended periods of time working in other states, and so may be required to pay state income taxes. If they live in other states for more than six months as well, residency usually falls within that state. However, by maintaining residency status utilizing the elements above, taxpayers can often keep their home state for tax purposes despite changing work requirements.
Those engaged in active military service are generally exempt from the various residency and work requirements. The state in which they signed up for the military is their home state for tax purposes, and no other state has the right to tax their military pay. The caveat is any compensation earned beyond military pay, which may be taxable if obtained by working in another state.