For federal tax purposes, you do not need to take any separate action to "enter" 414(h) contributions beyond simply recording your W-2 exactly as it is written. These are "employer pick-up" contributions to a government retirement plan that are already excluded from your federal taxable wages in Box 1 of your W-2.
However, if you live in New York, most of these contributions are taxable at the state level and require specific entry steps to ensure they are added back to your state income. In TurboTax, for the W2 Box 14 description, you must indicate if the amount is subject to NY tax or NY tax exempt. MOST are subject to NY tax, but if you are not sure, contact your employer.
**Say "Thanks" by clicking the thumb icon in a post
**Mark the post that answers your question by clicking on "Mark as Best Answer"