Summary—Local tumour control and survival is reported for 190 patients with T1 transitional cell cancer of the bladder who received a radical course of X‐ray therapy. There was no difference in survival by the histological grade of the cancer but patients with grade 3 cancers had the highest probability of local control. After initial complete local tumour regression there was a similar probability of subsequent distant metastases irrespective of the grade of the cancer.Radical small field beam directed radiotherapy is commended for patients with T1/pT1 grade 3 transitional cell cancer of the blad