United States Major Regions Postal Code Details

US United States Major Regions Postal Code Details

🏛️ Iowa

50002

Adair

Postal Range: 50002~50858

50839

Adams

Postal Range: 50839~50859

52140

Allamakee

Postal Range: 52140~52172

52544

Appanoose

Postal Range: 52544~52594

50025

Audubon

Postal Range: 50025~51543

52206

Benton

Postal Range: 52206~52354

50613

Black Hawk

Postal Range: 50613~50707

50031

Boone

Postal Range: 50031~50223

50622

Bremer

Postal Range: 50622~50677

50607

Buchanan

Postal Range: 50607~52329

50510

Buena Vista

Postal Range: 50510~51033

50602

Butler

Postal Range: 50602~50670

50538

Calhoun

Postal Range: 50538~51453

50058

Carroll

Postal Range: 50058~51463

50020

Cass

Postal Range: 50020~51552

52216

Cedar

Postal Range: 52216~52772

50401

Cerro Gordo

Postal Range: 50401~50482

51005

Cherokee

Postal Range: 51005~51061

50603

Chickasaw

Postal Range: 50603~52154

50174

Clarke

Postal Range: 50174~50275

51047

Clay

Postal Range: 51047~51366

52042

Clayton

Postal Range: 52042~52159

52037

Clinton

Postal Range: 52037~52777

51432

Crawford

Postal Range: 51432~51528

50003

Dallas

Postal Range: 50003~50276

52537

Davis

Postal Range: 52537~52584

50065

Decatur

Postal Range: 50065~50264

50654

Delaware

Postal Range: 50654~52330

52601

Des Moines

Postal Range: 52601~52660

51331

Dickinson

Postal Range: 51331~51364

52001

Dubuque

Postal Range: 52001~52099

50514

Emmet

Postal Range: 50514~51365

50606

Fayette

Postal Range: 50606~52175

50435

Floyd

Postal Range: 50435~50653

50041

Franklin

Postal Range: 50041~50633

51639

Fremont

Postal Range: 51639~51654

50050

Greene

Postal Range: 50050~51462

50609

Grundy

Postal Range: 50609~50680

50026

Guthrie

Postal Range: 50026~50277

50034

Hamilton

Postal Range: 50034~50595

50423

Hancock

Postal Range: 50423~50484

50006

Hardin

Postal Range: 50006~50672

51529

Harrison

Postal Range: 51529~51579

52630

Henry

Postal Range: 52630~52659

50466

Howard

Postal Range: 50466~52163

50519

Humboldt

Postal Range: 50519~50591

51006

Ida

Postal Range: 51006~51445

52203

Iowa

Postal Range: 52203~52361

52030

Jackson

Postal Range: 52030~52309

50028

Jasper

Postal Range: 50028~50251

52533

Jefferson

Postal Range: 52533~52635

52235

Johnson

Postal Range: 52235~52755

52205

Jones

Postal Range: 52205~52362

50104

Keokuk

Postal Range: 50104~52591

50451

Kossuth

Postal Range: 50451~50598

52619

Lee

Postal Range: 52619~52658

52202

Linn

Postal Range: 52202~52499

52640

Louisa

Postal Range: 52640~52754

50049

Lucas

Postal Range: 50049~50272

51230

Lyon

Postal Range: 51230~51246

50033

Madison

Postal Range: 50033~50273

50027

Mahaska

Postal Range: 50027~52595

50044

Marion

Postal Range: 50044~50256

50005

Marshall

Postal Range: 50005~50247

51533

Mills

Postal Range: 51533~51571

50426

Mitchell

Postal Range: 50426~50481

51010

Monona

Postal Range: 51010~51572

50150

Monroe

Postal Range: 50150~52569

50847

Montgomery

Postal Range: 50847~51591

52720

Muscatine

Postal Range: 52720~52778

51009

Obrien

Postal Range: 51009~51346

51232

Osceola

Postal Range: 51232~51354

51601

Page

Postal Range: 51601~51656

50515

Palo Alto

Postal Range: 50515~51358

51001

Plymouth

Postal Range: 51001~51062

50540

Pocahontas

Postal Range: 50540~50593

50007

Polk

Postal Range: 50007~50983

51501

Pottawattamie

Postal Range: 51501~51577

50112

Poweshiek

Postal Range: 50112~52232

50074

Ringgold

Postal Range: 50074~50863

50535

Sac

Postal Range: 50535~51466

52722

Scott

Postal Range: 52722~52809

51446

Shelby

Postal Range: 51446~51593

51003

Sioux

Postal Range: 51003~51250

50010

Story

Postal Range: 50010~50278

50173

Tama

Postal Range: 50173~52348

50833

Taylor

Postal Range: 50833~51646

50149

Union

Postal Range: 50149~50861

52535

Van Buren

Postal Range: 52535~52651

52501

Wapello

Postal Range: 52501~52566

50001

Warren

Postal Range: 50001~50241

52201

Washington

Postal Range: 52201~52621

50008

Wayne

Postal Range: 50008~52590

50501

Webster

Postal Range: 50501~50594

50424

Winnebago

Postal Range: 50424~50478

52101

Winneshiek

Postal Range: 52101~52168

51004

Woodbury

Postal Range: 51004~51111

50434

Worth

Postal Range: 50434~50459

50071

Wright

Postal Range: 50071~50599

📮US United States Regional Postal Code FAQ & Postal Regulations

📮 What is the format of a US ZIP code?

Standard format is 5 digits (e.g., 10001). Extended format is ZIP+4 (9 digits like 10001-1234) with a hyphen.

🔍 How to find the ZIP code for an address?

Use the USPS ZIP Code Lookup tool by entering the full address on the official USPS website.

⚠️ What happens if I use a wrong ZIP code?

Mail may be delayed, returned, or lost. For important documents, use USPS tracking and verify the ZIP code.

🔄 Do ZIP codes ever change?

Yes, USPS may update ZIP codes due to regional adjustments. Always confirm your ZIP code after an address change.

📦 Is a ZIP code required for international mail to the US?

Absolutely. Always include the US ZIP code at the end of the address (e.g., New York, NY 10001 USA).