Why are SEP- and SIMPLE IRAs reported differently than Traditional IRAs?
The IRS instructs that Traditional IRA contributions made between January 1 and April 15 and designated for the prior year should be combined with other contributions made for that year and reported that way on Schwab statements and Form 5498. But for SEP- and SIMPLE IRAs, only the contributions made in the calendar year (and not the additional contributions designated for the prior year) are shown both on statements and on Form 5498.