Ohio - Significance region: Local
| Wilson-Lenox House |
| Wilson, Samuel and Sally, House |
| Wilson's Mills Settlement District |
| Wilson, Valentine, House |
| Winameg Mounds |
| Winans, Dr. J. C., House |
| Winders Motor Sales Company |
| Windsor Corners District |
| Windsor Mills Christ Church Episcopal |
| Windsor Public School |
| Winegardner Village |
| Winterringer Building and House |
| Winter, William, Stone House |
| Winton Terrace Historic District |
| Wintzer, Charles, Building |
| Wise, Isaac M., Temple-Center |
| Wise, Peter, House |
| Wiswell Road Covered Bridge |
| Wittenberg University Historic District |
| Wolcott, Benajah, House |
| Wolf Creek Mound |
| Women's Christian Association |
| Wood Commercial Building |
| Woodland Avenue and West Side Railroad Powerhouse |
| Woodland Cemetery |
| Woodland Cemetery Association of Dayton Historic District |
| Woodland-Larchmere Commercial Historic District |
| Woodlawn Cemetery |
| Woodlawn Farm |
| Wood Old Homestead |
| Woodrow, William, House |
| Woodruff, Charles, House |
| Woodruff, William H., House |
| Woods, Tet, Building |
| Woodward Opera House |
| Wooster Block |
| Workman Works |
| Worthington Historical Society Museum |
| Worthington Historic District |
| Worthington Manufacturing Company Boardinghouse |
| Worthington Public Square |
| Worthington United Presbyterian Church |
| Wright Brothers Memorial Mound Group |
| Wright Company Factory |
| Wright, Daniel Thew, House |
| Wright, Dr. Aaron, House |
| Wright, Dr. John A., House |
| Wright, Horace, House |
| Wright, J.E. Farm |
| Wright, John, Mansion |
| Wright Library |
| Wright, Lyman, Building |
| Wright-Patterson Air Force Base Mound |
| Wright, Potter, House |
| Xenia Carnegie Library |
| Yager, John and Carrie, House |
| Yeager, John J., House |
| Yellow Springs Historic District |
| YMCA |
| Yondota Historic District |
| York Lodge No. 563 |
| York United Methodist Church |
| Yost Tavern |
| Young, Benjamin and Mary, House |
| Young, Capt., House |
| Young-Shaw House |
| Youngstown Country Club |
| Youngstown Foundry and Machine East Boardman Works |
| Young, Thomas F., House |
| Young Woman's Christian Association |
| Young Women's Christian Association of Cincinnati |
| Yuster Building |
| Zaleski Methodist Church Mound |
| Zanesville YWCA |
| Zellers-Langel House |
| Zettler Grocery and Hardware |
| Zimmerly House |
| Zimmerman Kame |
| Zion Episcopal Church |
| Zion Lutheran Church |
| Zion Lutheran Church |
| Zion Lutheran School |
| Zion's Evangelical Lutheran Church |
| Zoarville Bridge |
| Zollinger, S., Company Building |
| Zottman House |
| Zweig Building |
Data from United States Park Service and Wikidata
