IRS web-site, has information on IRA-based plans, 401(k) plans, IRC 403(b)/457 Plans, Designated Roth Accounts in 401(k) ans 403(b) Plans and other information.
IRA-Contributions for the current year can be made until 04/15 of the following year.
ROTH IRA-same as IRA.
Simple IRA-Calendar year basis, must be established by October 1 of the current year for the current year.
SEP-may be established up to the due date of the return including extensions.
401(k)-same as a SEP.
A 401(k) is a type of retirement plan that allows employees to save and invest for their own retirement. Through a 401(k), you can authorize your employer to deduct a certain amount of money from your paycheck before taxes are calculated, and to invest it in the 401(k) plan. Your money is invested in investment options that you choose from the ones offered through your company's plan. The federal government established the 401(k) in 1981 with special tax advantages, to encourage people to prepare for retirement. They get their catchy name from the section of the Internal Revenue Code which established them (you guessed it, section 401(k)).
A SEP is a simplified employee pension plan. A SEP plan provides employers with a simplified method to make contributions toward their employees’ retirement and, if self-employed, their own retirement. Contributions are made directly to an Individual Retirement Account or Annuity (IRA) set up for each employee (a SEP-IRA). See Publication 560 for detailed SEP information for employers and employees.
A SARSEP is a simplified employee pension (SEP) plan set up before 1997 that includes a salary reduction arrangement. Under a SARSEP, employees can choose to have the employer contribute part of their pay to their Individual Retirement Account or Annuity (IRA) set up under the SARSEP. A SARSEP may not be established after 1996. However, for SARSEPs set up before 1997, eligible employees hired after 1996 must be allowed to participate. See IRS Publication 560, Retirement Plans for Small Business (SEP, SIMPLE, and Qualified Plans) and the "Instructions for the Employer" and "Instructions for the Employee" in Form 5305A-SEP, Salary Reduction Simplified Employee Pension - Individual Retirement Accounts Contribution Agreement, for detailed information.
IRC 403(b) Plans
Certain employers are allowed to have Internal Revenue Service (IRC) 403(b) Tax-Sheltered Annuity plans. You are allowed to have a 403(b) plan if you are:
A public school, college or university,
A church,
A public hospital, or
A charitable entity tax-exempt under section 501(c)(3) of the Code.
Basically, 403(b) plans are similar to 401(k) plans maintained by for-profit entities. Just as with a 401(k) plan, a 403(b) plan lets employees defer some of their salary. In this case, their deferred money goes to a 403(b) plan sponsored by the employer. This deferred money generally does not get taxed by the federal government or by most state governments until distributed. This is just as it is with 401(k) plans. If you establish a 403(b) plan, you can have other retirement plans and you may need to file Form 5500.
Plans of deferred compensation described in IRC section 457 are available for certain state and local governments and non-governmental entities tax exempt under IRC 501. They can be either eligible plans under IRC 457(b) or ineligible plans under IRC 457(f). Plans eligible under 457(b) allow employees of sponsoring organizations to defer income taxation on retirement savings into future years. Ineligible plans may trigger different tax treatment under IRC 457(f).