S1 Corporation to Announce First Quarter 2010 Financial Results on May 5, 2010

NORCROSS, Ga., April 22, 2010 (GLOBE NEWSWIRE) -- S1 Corporation (Nasdaq:SONE),
a leading global provider of customer interaction financial and payment
solutions, today announced that it will release financial results for the first
quarter ended March 31, 2010 on May 5, 2010 after the close of the financial
markets. Chief Executive Officer Johann Dreyer and Chief Financial Officer Paul
Parrish will also host an investor conference call that day beginning at 5:00
p.m. Eastern time to discuss the results.

Participants may access the call by dialing (877) 899-9075 (United States) or
(706) 758-0819 (international) and entering passcode 70391633. Investors may
also access a live audio webcast of this conference call by visiting www.s1.com
and entering the Investor Relations section under "About S1".

A replay of the webcast will be available approximately two hours after the
conclusion of the call. A telephone replay will also be available approximately
two hours after the conclusion of the call through May 19, 2010. To access the
replay, please dial (800) 642-1687 or (706) 645-9291 and enter passcode
70391633.

About S1 Corporation

Leading banks, credit unions, retailers, and processors need technology that
adapts to the complex and challenging needs of their businesses. These
organizations want solutions that can respond quickly to changes in the
marketplace and help grow their businesses. For more than 20 years, S1
Corporation (Nasdaq:SONE) has been a leader in developing software products that
offer flexibility and reliability. Over 3,000 organizations worldwide depend on
S1 for payments, online banking, mobile banking, voice banking, branch banking
and lending solutions that deliver a competitive advantage. www.s1.com

Forward Looking Statements

This press release contains forward-looking statements within the safe harbor
provisions of the Private Securities Litigation Reform Act. These statements
include statements with respect to our financial condition, results of
operations and business. The words "believes," "expects," "may," "will,"
"should," "projects," "contemplates," "anticipates," "forecasts," "intends" or
similar terminology identify forward-looking statements. Forward-looking
statements may include projections of our revenue, expenses, Adjusted EBITDA,
capital expenditures, earnings per share, product development projects, future
economic performance or management objectives. These statements are based on our
beliefs as well as assumptions made using information currently available to us.
Because these statements reflect our current views concerning future events,
they involve risks, uncertainties and assumptions. Therefore, actual results may
differ significantly from the results discussed in the forward-looking
statements. The risk factors included in our reports filed with the Securities
and Exchange Commission (and available on our web site at www.s1.com or the
SEC's web site at www.sec.gov) provide examples of risks, uncertainties and
events that may cause our actual results to differ materially from the
expectations we describe in our forward-looking statements. Except as provided
by law, we undertake no obligation to update any forward-looking statement for
any reason, even if new information becomes available.

CONTACT: S1 Corporation
Investor Contact:
Paul M. Parrish, Chief Financial Officer
404.923.3500
paul.parrish@s1.com