Exhibit 99.1


FOR IMMEDIATE RELEASE
---------------------

                               Company Contact:   Bruce R. York
                                                  Vice President and CFO
                                                  (206) 733-8180

        CELLULAR TECHNICAL SERVICES ANNOUNCES FAVORABLE ARBITRATION AWARD

Seattle, June 26, 2001 - Cellular Technical Services Company, Inc. (Nasdaq NM
Symbol CTSC) ("CTS"), a leading provider of products and services for the
telecommunications industry, today announced the conclusion of an arbitration
proceeding it had initiated against a former customer. Under the terms of the
arbitration award, which is subject to appeal, CTS is to receive damages and
interest totaling approximately $1.0 million or approximately $0.44 cents per
share, plus attorney's fees.

Stephen Katz, CTS Chairman and CEO stated, "A negotiated settlement would have
been preferred, but unfortunately that was not possible. The timing for
recognition of the income will be determined by the finalization of all events
of the award including the timing of the payment to be received and any appeals
process."

CTS provides real-time information processing and management solutions for the
telecommunications industry. Over the past 12 years, CTS has used its extensive
experience with real-time wireless call processing to create technologically
advanced solutions for this industry, including integrated solutions for fraud
management. Today, CTS is building a more diversified, vertically structured
organization with a focus on providing a wide range of products and services.

SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS: This press release may
contain forward-looking statements within the meaning of the Private Securities
Litigation Reform Act of 1995 that involve risks and uncertainties that could
cause actual results for CTS or its affiliates to differ materially from those
expressed or implied in the applicable statements. These risks and uncertainties
include but are not limited to: dependence on analog cellular networks for
certain products and services; vulnerability to rapid industry change and
technological obsolescence; limited customer base and reliance on a relatively
small number of customers and customer contracts; dependence on a limited number
of existing products and services; uncertainty of continued demand for and
market penetration of its existing products and services under existing and
future contracts; uncertainty in its ability to timely develop, introduce and
gain acceptance of new products and services; uncertainty of the demand for and
market penetration of new products and services; the possible impact of
competitive products and pricing; the risk that its current and future products
may contain errors or be affected by technical problems that would be difficult
and costly to detect and correct; manufacturing difficulties, including reliance
on a limited number of outside vendors for key components and processes;
potential difficulties in managing changing business conditions; dependence on
key personnel; the availability of financing; and other risks described in CTS'
filings with the Securities and Exchange Commission.