Why have my taxable social security benefits more than doubled from last year

Did you change your filing status from Married Filing Jointly to Married Filing Separately?  If so, that will cause your Social Security benefits to become 85% taxable.

The other reason could be a slight increase in income could have put you into the 85% taxable from the 50% taxable. Sometimes only a few dollars will make a difference. 

If you fall into the following, 85% of your social security is taxable income

• Single with income above $34,000
• Married Filing Jointly with income above $44,000
• Married Filing Separate regardless of income

If you fall into the following, 50% of your social security is taxable income

• Single with combined income between $25,000-$34,000
• Married Filing Jointly with combined income between $32,000 and $44,000

Your combined income is calculated by adding your

• AGI plus
• Nontaxable Interest plus
• 1/2 of your social security Benefits

Social Security Benefits Taxes