Columbus Day is a federal holiday in the United States, observed on the second Monday in October. However, not all states celebrate it as a legal holiday, and some have replaced it with other holidays. Here is a breakdown of how each state observes Columbus Day, according to the most relevant search results:

• Alabama: Yes
• Alaska: No
• Arizona: Yes
• Arkansas: Yes
• California: No, replaced by Indigenous Peoples Day in some cities
• Colorado: No, replaced by Cabrini Day in 2020
• Connecticut: Yes, celebrated as Italian Heritage Day in New Haven
• Delaware: No, not a legal holiday
• Florida: No
• Georgia: Yes
• Hawaii: No, Indigenous Peoples Day is celebrated on the 2nd Monday in October, but it is not a legal holiday
• Idaho: Yes
• Illinois: Yes
• Indiana: Yes
• Iowa: No, but the governor is authorized and requested by statute to proclaim the day
• Kansas: Yes
• Kentucky: Yes
• Louisiana: No, but some cities celebrate it
• Maine: Yes, celebrated as Indigenous Peoples Day
• Maryland: Yes
• Massachusetts: Yes, celebrated as Indigenous Peoples Day in some cities
• Michigan: No, but some cities celebrate it
• Minnesota: No, but some cities celebrate it
• Mississippi: Yes
• Missouri: Yes
• Montana: Yes
• Nebraska: Yes
• Nevada: No, but the governor is authorized and requested by statute to proclaim the day
• New Hampshire: Yes
• New Jersey: Yes
• New Mexico: No, replaced by Indigenous Peoples Day
• New York: Yes
• North Carolina: No, but some cities celebrate it
• North Dakota: Yes
• Ohio: Yes
• Oklahoma: Yes
• Oregon: No, but some cities celebrate it
• Pennsylvania: Yes, celebrated as Indigenous Peoples Day in Philadelphia
• Rhode Island: Yes
• South Carolina: No
• South Dakota: Yes, celebrated as Native Americans Day
• Tennessee: No, but the governor can move the observance to the Friday after Thanksgiving
• Texas: Yes
• Utah: Yes
• Vermont: No, replaced by Indigenous Peoples Day
• Virginia: Yes, celebrated as Columbus Day and Yorktown Victory Day
• Washington: No, but the governor is authorized and requested by statute to proclaim the day
• West Virginia: Yes
• Wisconsin: No
• Wyoming: Yes

In summary, 16 states and American Samoa territory observe Columbus Day as a public holiday, while 13 states and Washington, D.C. do not officially celebrate it. Some states have replaced Columbus Day with Indigenous Peoples Day, while others celebrate both or have a different holiday altogether.