EXHIBIT 23 ---------- CONSENT OF INDEPENDENT ACCOUNTANTS We hereby consent to the incorporation by reference in the Registration Statement on Form S-8 (No. 333-37959 and 333-38137) RCN Corporation of our report dated June 28, 2000 relating to the financial statements of RCN Savings & Stock Ownership Plan for the year ended December 31, 1999, which appears in this Form 11-K. /s/ PricewaterhouseCoopers LLP Philadelphia, Pennsylvania June 28, 2000