701—40.23(422) Social security benefits. For tax years beginning on or after January 1, 1984, but before January 1, 2014, social security benefits received are taxable on the Iowa return. Although Tier 1 railroad retirement benefits were taxed similarly as social security benefits for federal income tax purposes beginning on or after January 1, 1984, these benefits are not subject to Iowa income tax. 45 U.S.C. Section 231m prohibits taxation of railroad retirement benefits by the states.
The following subrules specify how social security benefits are taxed for Iowa individual income tax purposes for tax years beginning on or after January 1, 1984, but prior to January 1, 1994; for tax years beginning on or after January 1, 1994, but prior to January 1, 2007; and for tax years beginning on or after January 1, 2007, but prior to January 1, 2014:
	40.23(1) Taxation of social security benefits for tax years beginning on or after January 1, 1984, but prior to January 1, 1994. For tax years beginning on or after January 1, 1984, but prior to January 1, 1994, social security benefits are taxable on the Iowa return to the same extent as the benefits are taxable for federal income tax purposes. When both spouses of a married couple receive social security benefits and file a joint federal income tax return but separate returns or separately on the combined return form, the taxable portion of the benefits must be allocated between the spouses. The following formula should be used to compute the amount of social security benefits to be reported by each spouse on the Iowa return:

Taxable Social Security Benefits on the Federal Return	×	Total Social Security Benefit Received by Husband (or Wife)	
		Total Social Security Benefits Received by Both Spouses	
The example shown below illustrates how taxable social security benefits are allocated between spouses:
A married couple filed a joint federal income tax return for 1984. They filed separately on the combined return form for Iowa income tax purposes. During the tax year the husband received $6,000 in social security benefits and the wife received $3,000 in social security benefits. $2,000 of the social security benefits was taxable on the federal return.
The $2,000 in taxable social security benefits is allocated to the spouses on the following basis:

Husband	 	Wife	
$2,000	×	$6,000	=	$1,333.40		$2,000	×	$3,000	=	$666.60	
		$9,000						$9,000			
In situations where taxpayers have received both social security benefits and Tier 1 railroad retirement benefits and are taxable on a portion of those benefits, the formula which follows should be used to determine the social security benefits to be included in net income:

Taxable Social Security Benefits and Railroad Retirement Benefits on Federal Return	×	Total Social Security Benefit Received	
		Total Social Security Benefits and Railroad Retirement Benefits Received	
	40.23(2)  Taxation of social security benefits for tax years beginning on or after January 1, 1994, but prior to January 1, 2007. For tax years beginning on or after January 1, 1994, but prior to January 1, 2007, although up to 85 percent of social security benefits received may be taxable for federal income tax purposes, no more than 50 percent of social security benefits will be taxable for state individual income tax purposes. Thus, in the case of Iowa income tax returns for 1994 through 2006, social security benefits will be taxed as the benefits were taxed from 1984 through 1993 as described in subrule 40.23(1).
The amount of social security benefits that is subject to tax is the lesser of one-half of the annual benefits received in the tax year or one-half of the taxpayer’s provisional income over a specified base amount. The provisional income is the taxpayer’s modified adjusted gross income plus one-half of the social security benefits and one-half of the railroad retirement benefits received. Although railroad benefits are not taxable, one-half of the railroad retirement benefits received may be used to determine the amount of social security benefits that is taxable for state income tax purposes. Modified adjusted gross income is the taxpayer’s federal adjusted gross income, plus interest that is tax-exempt on the federal return, plus any of the following incomes:
	1.	Savings bond proceeds used to pay expenses of higher education excluded from income under Section 135 of the Internal Revenue Code.
	2.	Foreign source income excluded from income under Section 911 of the Internal Revenue Code.
	3.	Income from Guam, American Samoa, and the Northern Mariana Islands excluded under section 931 of the Internal Revenue Code.
	4.	Income from Puerto Rico excluded under Section 933 of the Internal Revenue Code.
A taxpayer’s base amount is: (a) $32,000 if married and a joint federal return was filed, (b) $0 if married and separate federal returns were filed by the spouses and (c) $25,000 for individuals who filed federal returns and used a filing status other than noted in (a) and (b).
The IA 1040 booklet and instructions for 1994 through 2006 will include a worksheet to compute the amount of social security benefits that is taxable for Iowa income tax purposes. An example of the social security worksheet follows. Similar worksheets will be used for computing the amount of social security benefits that is taxable for years 1995 through 2006. An example of the social security worksheet follows:

1. Enter amount(s) from box 5 of all of Form(s) SSA-1099. If a joint return was filed, enter totals from box 5 of Form(s) SSA-1099 for both spouses. Do not include railroad retirement benefits from RRB-1099 here. See line 3.	1. 		
2. Divide line 1 amount above by 2.	2. 		
*3. Add amounts of the following incomes from Form 1040: wages, taxable interest income, dividend income, taxable state and local income tax refunds, alimony, business income or loss, capital gain or loss, capital gain distributions, other gains, taxable IRA distributions, taxable pensions and annuities, incomes from Schedule E, farm income or loss, unemployment compensation, other income and 1/2 of railroad retirement benefits from RRB 1099.	3. 		
4. Enter amount from Form 1040, line 8b for interest that is federally tax-exempt.	4. 		
5. Add lines 2, 3 and 4.	5. 		
6. Enter total adjustment to income from Form 1040.	6. 		
7. Subtract line 6 from line 5.	7. 		
8. Enter on line 8 one of the following amounts based on the filing status used on Form 1040: Single, Head of Household, or Qualifying Widow(er), enter $25,000. Married filing jointly, enter $32,000. Married filing separately, enter $0 ($25,000 if you did not live with spouse any time in 1994).	8. 		
9. Subtract line 8 from line 7. If zero or less enter 0. If line 9 is zero, none of the social security benefits are taxable. If line 9 is more than zero, go to line 10.	9. 		
10. Divide line 9 amount above by 2.	10. 		
11. Taxable social security benefits enter smaller of line 2 or line 10 here and on line 14 IA 1040.	11. 		
*If applicable, include on line 3 the following incomes excluded from federal adjusted gross income: foreign earned income, income excluded by residents of Puerto Rico, American Samoa, and Guam and proceeds from savings bonds used for higher education.
Married taxpayers who filed a joint federal return and are filing separate Iowa returns or separately on the combined return form can allocate taxable social security benefits between them with the following formula.

Taxable Social Security Benefits From Worksheet	×	Total Social Security Benefit Received by Husband (or Wife)	
		Total Social Security Benefits Received by Both Spouses	
	40.23(3) Taxation of social security benefits for tax years beginning on or after January 1, 2007, but prior to January 1, 2014. For tax years beginning on or after January 1, 2007, but prior to January 1, 2014, the amount of social security benefits subject to Iowa income tax will be computed as described in subrule 40.23(2), but will be further reduced by the following percentages:

Calendar years 2007 and 2008	32%	
Calendar year 2009	43%	
Calendar year 2010	55%	
Calendar year 2011	67%	
Calendar year 2012	77%	
Calendar year 2013	89%	
The Iowa individual income tax booklet and instructions for 2007 through 2013 will include a worksheet to compute the amount of social security benefits that is taxable for Iowa income tax purposes. An example of the social security worksheet follows:

1. Enter amount(s) from box 5 of Form(s) SSA-1099. If a joint return was filed, enter totals from box 5 of Form(s) SSA-1099 for both spouses. Do not include railroad retirement benefits from RRB-1099 here. See line 3.	1. 		
2. Divide line 1 amount above by 2.	2. 		
*3. Add amounts of the following incomes from Form 1040: wages, taxable interest income, dividend income, taxable state and local income tax refunds, alimony, business income or loss, capital gain or loss, capital gain distributions, other gains, taxable IRA distributions, taxable pensions and annuities, incomes from Schedule E, farm income or loss, unemployment compensation, other income and 1/2 of railroad retirement benefits from RRB 1099.	3. 		
4. Enter amount from Form 1040, line 8b for interest that is federally tax-exempt.	4. 		
5. Add lines 2, 3 and 4.	5. 		
6. Enter total adjustment to income from Form 1040.	6. 		
7. Subtract line 6 from line 5.	7. 		
8. Enter on line 8 one of the following amounts based on the filing status used on Form 1040: Single, Head of Household, or Qualifying Widow(er), enter $25,000. Married filing jointly, enter $32,000. Married filing separately, enter $0 ($25,000 if you did not live with spouse anytime during the year).	8. 		
9. Subtract line 8 from line 7. If zero or less enter 0. If line 9 is zero, none of the social security benefits are taxable. If line 9 is more than zero, go to line 10.	9. 		
10. Divide line 9 amount above by 2.	10. 		
11. Taxable social security benefits before phase-out exclusion. Enter smaller of line 2 or line 10.	11. 		
12. Multiply line 11 by applicable exclusion percentage.	12. 		
13. Taxable social security benefits. Subtract line 12 from line 11.	13. 		
*If applicable, include on line 3 the following incomes excluded from federal adjusted gross income: foreign earned income, income excluded by residents of Puerto Rico, American Samoa, and Guam and proceeds from savings bonds used for higher education and employer-provided adoption benefits.
Married taxpayers who filed a joint federal return and are filing separate Iowa returns or separately on the combined return form can allocate taxable social security benefits between them with the following formula.

Taxable Social Security Benefits From Worksheet	×	Total Social Security Benefit
Received by Spouse 1 (or Spouse 2)	
		Total Social Security Benefits
Received by Both Spouses	
The amount on line 12 of this worksheet is the phase-out exclusion of social security benefits which must be included in net income in determining whether an Iowa return must be filed in accordance with rules 701—39.1(422) and 701—39.5(422), and this amount must also be included in net income in calculating the special tax computation in accordance with rule 701—39.15(422).
	40.23(4) Taxation of social security benefits for tax years beginning on or after January 1, 2014. For tax years beginning on or after January 1, 2014, no social security benefits are taxable on the Iowa return. However, the 100 percent phase-out exclusion of social security benefits must still be included in net income in determining whether an Iowa return must be filed in accordance with rules 701—39.1(422) and 701—39.5(422), and the 100 percent phase-out exclusion of social security benefits must also be included in net income in calculating the special tax computation in accordance with rule 701—39.15(422).
This rule is intended to implement Iowa Code section 422.7 as amended by 2006 Iowa Acts, Senate File 2408.