Exhibit 99.1
STONE ENERGY CORPORATION
Announces 2011 Capital Expenditure Budget Increase and Updated Production Guidance
LAFAYETTE, LA. May 25, 2011
Stone Energy Corporation (NYSE: SGY) announced that its Board of Directors has increased the 2011
capital expenditure budget from $425 million to a range of $475 — $500 million due to a projected
increase in production, oil prices and estimated cash flow, combined with an attractive inventory
of capital projects. In addition, Stone announced it has increased its 2011 production guidance
from 200 — 220 million cubic feet of gas equivalent (MMcfe) per day up to 205 — 225 MMcfe per
day. Stone expects to fund substantially all of its increased capital expenditure budget with
operating cash flow.
Forward Looking Statements
Certain statements in this press release are forward-looking and are based upon Stone’s current
belief as to the outcome and timing of future events. All statements, other than statements of
historical facts, that address activities that Stone plans, expects, believes, projects, estimates
or anticipates will, should or may occur in the future, including future production of oil and gas,
future capital expenditures and drilling of wells and future financial or operating results are
forward-looking statements. Important factors that could cause actual results to differ materially
from those in the forward-looking statements herein include the timing and extent of changes in
commodity prices for oil and gas, operating risks, liquidity risks, political and regulatory
developments and legislation, including developments and legislation relating to our operations in
the Gulf of Mexico and Appalachia, and other risk factors and known trends and uncertainties as
described in Stone’s Annual Report on Form 10-K and Quarterly Reports on Form 10-Q as filed with
the SEC. Should one or more of these risks or uncertainties occur, or should underlying assumptions
prove incorrect, Stone’s actual results and plans could differ materially from those expressed in
the forward-looking statements.
Estimates for Stone’s future production volumes are based on assumptions of capital expenditure
levels and the assumption that market demand and prices for oil and gas will continue at levels
that allow for economic production of these products. The production, transportation and marketing
of oil and gas are subject to disruption due to transportation and processing availability,
mechanical failure, human error, hurricanes and numerous other factors. Stone’s estimates are
based on certain other assumptions, such as well performance, which may vary significantly from
those assumed. Delays experienced in well permitting could affect the timing of drilling and
production. Lease operating expenses, which include major maintenance costs, vary in response to
changes in prices of services and materials used in the operation of our properties and the amount
of maintenance activity required. Estimates of DD&A rates can vary according to reserve additions,
capital expenditures, future development costs, and other factors. Therefore, we can give no
assurance that our future production volumes, lease operating expenses or DD&A rates will be as
estimated.
Stone Energy is an independent oil and natural gas exploration and production company headquartered
in Lafayette, Louisiana with additional offices in New Orleans, Houston and Morgantown, West
Virginia. Our business strategy is to leverage cash flow generated from existing assets to maintain
relatively stable GOM shelf production, profitably grow gas reserves and production in
price-advantaged basins such as Appalachia and the Gulf Coast Basin, and profitably grow oil
reserves and production in material impact areas such as the deep water GOM and the Rocky Mountain
region. For additional information, contact Kenneth H. Beer, Chief Financial Officer, at
337-521-2210 phone, 337-521-9880 fax or via e-mail at CFO@StoneEnergy.com.