See: https://www1.nyc.gov/site/opa/taxes/tax-frequently-asked-questions.page
For Pension Plans:
Contributions are shown in Box 14,
IRC414H. Pension contributions are not subject to federal income tax,
but are subject to state, city, Social Security, and Medicare taxes. You
need to add the pension contribution shown in Box 14 to the reported
wage amount.
For Health Insurance Premiums, Dependent Care Assistance Program (DeCAP), and Health Care Flexible Spending Account (HCFSA):The
amounts for these programs, covered under Section 125 of the IRS code,
are reflected in Box 14, IRC125. The amount for DeCAP is shown also in
Box 10. They are not subject to federal, Social Security, and Medicare
taxes. The reduction in earnings shows on your W-2 but not on your pay
statement.
The amount in the IRC 125 Box is subject to New York
State and City taxes. The NYS income tax instructions direct the income
tax filer to report wages as they appear on the W-2 in Box 1 then to add
back the amount to arrive at New York State/City taxable wages.