The 1973 National Soccer League season was the fiftieth season under the National Soccer League (NSL) name. The season began in May and concluded in late October with Toronto Hungaria defeating Toronto Croatia for the NSL Championship. Toronto Hungaria repeated their success by defeating Croatia for the NSL Cup, which marked the organization's first league double. Although Toronto Croatia was defeated in the postseason, they still managed to secure the regular-season title and qualified for the Canadian Open Cup. In the Canadian Open Cup final Toronto successfully defended the title for the third consecutive season by defeating Challenge Trophy finalists Toronto West Indies United.