S.D. Codified Laws § 5-22-2
Every person wishing to avail himself of the provisions of the statutes providing liens on proceeds of public improvement contracts shall, within twenty days after any item claimed by him shall have been furnished or any work done by him shall have been performed, file with the officer of such public body who is by law made the custodian of its official records, a just and true account of the demand due or to become due him after allowing all credits and verified by his affidavit. A failure to file the same within the time aforesaid shall not defeat the lien upon the amount remaining due to the contractor at the time of filing. If any person who shall have performed labor or furnished materials as provided in this chapter shall procure from the contractor a settlement and statement of his account, signed by the contractor and verified by his own affidavit, the same may be filed and shall have the same force and effect as the account heretofore mentioned.
SDCL 5-22-2