Amendment dated March 5, 2019 to Convertible Promissory Note issued to Tangiers Global, LLC dated January 31, 2019

1.

Payment. The Lender shall make a payment to the Borrower $150,000 of Consideration, plus $15,000 in an OID under the Note on or before March 4, 2019.

2.

Use of Proceeds. The Company covenants that it will within, three months of the Effective Date of this Consideration, it shall use approximately $150,000 of the proceeds in the manner set forth below (the “Use of Proceeds”): general working capital.

3.

Independent Transactions. The Borrower understands and agrees that the Note sets forth the terms for a series of independent transactions in which the Lender may elect to make a payment of Consideration to the Borrower with each payment of Consideration creating a separate obligation of the Borrower to the Lender with the terms set forth in the Note. Accordingly, the Maturity Date of each payment of Consideration, and the repayment terms for each payment of Consideration, are as set forth in the Note.

4.

The Borrower confirms that it has not undertaken any capital raise, whether through debt or equity, with any other party since the Effective Date of the Note.

/s/Dennis P. Calvert

/s/Justin Ederle

BioLargo, Inc.

Tangiers Global, LLC

By: Dennis P. Calvert

By: Justin Ederle

Its: President

Its: Managing Member

Date: March 5, 2019

Date: March 6, 2019

TO:

Tangiers Global, LLC

FROM:

BioLargo, Inc.

DATE:

March 4, 2019

Please disburse to:

Amount to disburse:

$150,000

Form of distribution

Wire

Name

BioLargo, Inc.

Address

Wire Instructions:

FBO: BioLargo, Inc.

Account #: 001549768543

ABA Routing #:#

Bank of America, attention: Branch Manager

Address: 24211 Paseo De Valencia, Laguna Hills, CA 92653

Phone: 949 ###-###-####