N.H. Rev. Stat. § 35-A:28
All banks, trust companies, savings banks, investment companies and other persons carrying on a banking business are hereby authorized to give to the bank a good and sufficient undertaking with such securities as shall be approved by the bank to the effect that such bank or banking institution as hereinbefore described shall faithfully keep and pay over to the order of or upon the warrant of the bank or its authorized agent all such funds as may be deposited with it by the bank and agreed interest thereon under or by reason of this chapter, at such times or upon such demands as may be agreed with the bank or in lieu of such sureties, deposit with the bank or its authorized agent or any trustee therefor or for the holders of any bonds, as collateral, such securities as the bank may approve. The deposits of the bank may be evidenced by an agreement in such form and upon such terms and conditions as may be agreed upon by the bank and such bank or banking institution.
RSA 35-A:28
1977, 491:1, eff. July 1, 1977.