Exhibit 21.1 SUBSIDIARIES OF TERAWULF INC. The registrant’s subsidiaries as of December 31, 2025 are set forth in the list below: Legal Entity Name Percentage of Voting Securities Owned Directly or Indirectly by Registrant Jurisdiction of Organization Abernathy Data LLC 50.1% Delaware Akela Data LLC 100% Delaware Akela Data Holdings LLC 100% Delaware Beowulf Electricity & Data LLC 100% Delaware Beowulf E&D (MD) LLC 100% Delaware Beowulf (E&D (NY) LLC 100% Delaware Big Country Wulf LLC 100% Delaware Chesapeake Data LLC 100% Delaware Flash Compute LLC 50.1% Delaware FS CS I LLC 50.1% Delaware Justified DataPower LLC 100% Delaware Kyalami Data LLC 100% Delaware Lake Hawkeye LLC 100% Delaware Lake Mariner Data LLC 100% Delaware La Lupa Data LLC 100% Delaware TeraCub Inc. 100% Delaware TeraLease LLC 100% Delaware TeraWulf Brookings LLC 100% Delaware TeraWulf Ploughwind LLC 100% Delaware TeraWulf (Thales) LLC 100% Delaware WULF Compute LLC 100% Delaware WULF Compute Lease LLC 100% Delaware