N.H. Rev. Stat. § 23:16

I. The trustees shall have the custody of all trust funds held by their county. II. The funds shall be invested only in bonds, notes or other obligations of the United States government, or in state, county, town, city, school district, water and sewer district bonds and the notes of towns or cities in this state; and such stocks and bonds as are legal for investment by New Hampshire banks and when so invested, the trustees shall not be liable for the loss thereof; in any common trust fund established by the New Hampshire Charitable Foundation in accordance with RSA 292:23; and in deposits, including money market accounts, or certificates of deposit, or repurchase agreements, and all other types of interest bearing accounts, of federally insured banks authorized to accept deposits under RSA 6:8, I and I-a. The trustees may retain investments as received from donors until the maturity thereof. III. Deposits in banks shall be made in the name of the county which holds the same in trust, and it shall appear upon the book thereof that the same is a trust fund.