- Offer tax-advantage options.
- Have the same contribution limits.
- Offer Roth options.
- Require participants be 59.5 to withdraw from plan.
- Grow tax-deferred.
- type of employer that is sponsoring the plan
- A 401k is often administered by one company. In a 403b the organization also has no ownership of the 403b plan.
- 403b generally exempt from the Employee Retirement Income Security Act (ERISA).
Additional Information here.