Who must file an Alabama individual income tax return?
Full year residents whose filing status is “Single” must file
if gross income for the year is at least $4,000. Full year residents
whose filing status is “Married Filing Separate Return” must file if
gross income for the year is at least $5,250. Full year residents whose
filing status is Head of Family” must file if gross income for the year
is at least $7,700. Those whose filing status is “Married Filing Joint
Return” and whose gross income for the year is at least $10,500 must
file an Alabama income tax return.
https://revenue.alabama.gov/individual-corporate/faq/individual-income-tax/
It refers to "gross income" and does not distinguish between taxable income, so based on instructions, you would need to file a AL. return.
