Filed under Rule 424(b)(3), Registration Statement No. 333-249702

Pricing Supplement No. 550 - Dated Monday, September 12, 2022 (To: Prospectus Dated October 28, 2020 and Prospectus Supplement Dated October 30, 2020

CUSIP Number

Principal Amount

Selling Price

Gross Concession

Net Proceeds

Coupon Type

Coupon Rate

Coupon Frequency

Maturity Date

1st Coupon Date

1st Coupon Amount

Survivor's Option

Product Ranking

63743FT48

[]

100.000%

1.550%

[]

Fixed

4.000%

Monthly

09/15/2030

10/15/2022

$2.56

Yes

Senior Unsecured Notes

Redemption Information: Callable at 100% on 9/15/2024 and Monthly thereafter with 30 Calendar Days' Notice.

National Rural Utilities Cooperative Finance Corp Offering Date: Monday, September 12, 2022 through Monday, September 19, 2022 Trade Date: Monday, September 19, 2022 @12:00 PM ET Settle Date: Thursday, September 22, 2022 Minimum Denomination/Increments:$1,000.00/$1,000.00 Initial trades settle flat and clear SDFS: DTC Book Entry only DTC Number: 0235 via RBC Dain Rauscher Inc. Agents: InspereX LLC, Citigroup, Wells Fargo Advisors, RBC Capital Markets Trustee: U.S. Bank National Association   If the maturity date or an interest payment date for any note is not a business day (as term is defined in prospectus), principal, premium, if any, and interest for that note is paid on the next business day, and no interest will accrue from, and after, the maturity date or interest payment date. InterNotes® is a registered trademark of InspereX Holdings LLC. All Rights Reserved. National Rural Utilities Cooperative Finance Corp  
Prospectus dated October 28, 2020 and  
Prospectus Supplement Dated: October 30, 2020