IRS Withholding Calculator

https://apps.irs.gov/app/withholdingcalculator/

ITIN

https://www.irs.gov/individuals/general-itin-information

Where’s My Refund?

https://www.irs.gov/refunds

Where’s My MA Refund?

http://www.mass.gov/dor/individuals/

Federal Tax Calendar

https://www.irs.gov/pub/irs-pdf/p509.pdf

MA Department of Revenue (DOR) Tax Calendar

http://www.mass.gov/dor/tax-professionals/current-year-tax-information/tax-calendar/tax-calendar.html