Yes, charter fishing is a retail recreational service. Persons engaged in service activities, even those services defined as retail sales, must pay sales tax or use tax on all items used by them in providing the retail service.
Starting October 1: Some business services are now subject to retail sales tax, as required by state law, ESSB 5814. When you buy these services, vendors should add sales tax to your bill. If you sell these services, you should begin collecting retail sales tax. Learn more about Services newly subject to retail sales tax.