2026 Guidance and Operations Update

Colombia Program Focused on Maximizing Free Cash Flow

Development Program Focused on Quick Payouts and Capital Efficient Projects

2026 Capital Program Fulfills Commitments Over the Suroriente Block

Reported Current Company Production of 48,000 to 49,000 BOEPD

CALGARY, Alberta, Dec. 10, 2025 (GLOBE NEWSWIRE) -- Gran Tierra Energy Inc. (“Gran Tierra” or the “Company”) (NYSE American:GTE) (TSX:GTE) (LSE:GTE) today announced its 2026 capital budget, production guidance and operational update. All dollar amounts are in United States dollars and all production volumes are on a working interest before royalties basis and are expressed in barrels of oil equivalent (“boe”) per day (“BOEPD”), unless otherwise stated.

Message to Shareholders

Gary Guidry, President and Chief Executive Officer of Gran Tierra, commented: “With our exploration commitments in Ecuador now completely fulfilled during 2025 and the Suroriente carried work program forecast to be completed by early Q2 2026, Gran Tierra is entering a new phase focused on generating free cash flow and maximizing the value of our diversified portfolio. Our 2026 capital program is focused on high-return, quick-payout development projects across both South America and Canada, including the upcoming production well drilling program in Cohembi and the Montney program at Simonette.

Based on our 2026 budget, we see a clear path to fully addressing the $180 million amortization of our 2029 notes due in October 2026 while continuing to optimize long-term value of our asset portfolio. Beyond 2026, Gran Tierra maintains a clear path to meeting all debt maturities, supported by strong liquidity, a resilient cash-generating asset base and commitment to generating free cash flow.

The successful closing of the Perico and Espejo acquisition further enhances and strengthens our portfolio in Ecuador, especially as we integrate development plans with our Iguana discovery to unlock meaningful operational and cost synergies. Gran Tierra expects production in Ecuador to exit 2025 at approximately 8,500 to 9,500 bopd with corporate production of approximately 48,000 to 49,000 boepd. Gran Tierra is well-positioned for a period of sustained free cash flow generation and disciplined, return-focused execution.”

Key Highlights:

2026 Guidance

*Canada’s production is comprised of approximately 47% natural gas, 21% oil and 32% natural gas liquids (“NGL”)

Free Cash Flow2 Generation a Key Focus: With all 2025 Ecuador exploration commitments fulfilled and most Suroriente Continuation obligations complete, Gran Tierra is shifting its focus to generating free cash flow2 while maximizing portfolio value. Recent exploration success and the strong performance of its core assets provide a substantial reserve base to support ongoing free cash flow2 generation. The Company’s Ecuador portfolio has reached an inflection point, moving from exploration to development as we integrate recent discoveries and advance multi-year growth opportunities. Based on existing assets, Gran Tierra is targeting over $75-$150 million of free cash flow per year from 2027 onwards at a long-term real Brent price of $70 per bbl.

2026 Base Capital Program: The program will focus on quick payback development projects with a focus on free cash flow2 generation.

Development: Gran Tierra expects to drill a total of 8 to 10 gross development wells in its 2026 capital program, including:

Suroriente: The Company plans to drill 4 gross development wells in the Cohembi oil field located in the Southern Putumayo Basin of Colombia. With the completion of this drilling program Gran Tierra expects to completely fulfill its commitments associated with the Suroriente Continuation. Upon completion of the commitments, the economics of the Suroriente block strengthen for Gran Tierra and its Partner paying its working interest share of operating and capital costs.

Simonette: Gran Tierra plans to drill 5 gross (2.5 net) wells in South Simonette targeting oil weighted-Montney production.

Structural Cost Saving Initiatives: Structural cost initiatives are underway across the portfolio, focused on rationalizing workover activity, improving procurement terms and reducing costs through operational optimization and planning. Gran Tierra maintains a disciplined and constant focus on process improvement, ensuring that small operational changes accumulate into meaningful structural cost savings. Collectively, these actions support a stronger, more efficient cost profile across the organization.

Repayment of $180 Million of Debt in October 2026:

As part of the Company’s ongoing strategy to reduce debt, Gran Tierra has repurchased $20 million of its 2029 Notes during the year, reducing the October 2026 amortization to $180 million while lowering the outstanding balance to $718 million.

Gran Tierra intends to fully address the $180 million scheduled amortization related to the 2029 notes coming due in October 2026. Based on the Company’s 2026 expected free cash flow2 generation, disciplined capital program, and continued focus on operational efficiency provide a clear path to meeting this obligation under any of the provided cases – Low, Base and High. Gran Tierra’s planning assumptions incorporate this repayment as a core use of free cash flow in addition to its available credit facilities of approximately $67 million stated as of September 30, 2025, and previously announced $150 million prepayment facility.

Gran Tierra is targeting to reach Net Debt to EBITDA to be below 1.5x in 2028 and below 1.0 by the end of 2029. The Company’s long-term plan, coupled with disciplined capital spending and growing free cash flow, underpins our confidence in fully repaying our debt as scheduled while growing EBITDA.

Hedging: Gran Tierra also employs a disciplined, risk-managed hedging strategy designed to protect cash flow, support capital planning, and enhance financial stability across commodity cycles. Gran Tierra maintains a rolling 12-month hedging program and typically hedges 30–50% of forecast production over the next six months, and 20–30% over the subsequent six-month period.

Close of Acquisition of Perico and Espejo Blocks in Ecuador

Gran Tierra has closed the previously announced strategic acquisition of the Perico and Espejo Blocks in Ecuador, following approval from the Ecuador Ministry of Environment and Energy. The transaction shall follow with customary post-closing regulatory requirements including the authorization of the amendment of the underlying Perico and Espejo block contracts after the approval of the Comité de Licitaciones Hidrocarburíferas.

Following Gran Tierra’s 2025 discoveries on the adjacent Iguana Block, the Company believes that developing the Perico and Iguana Blocks together will capture meaningful operational and cost synergies.

Operations Update

Current Production: The Company’s current production5 is approximately 48,000 to 49,000 boepd.

Ecuador

Conejo A-2: The Hollin oil zone was perforated over 41 feet (“ft”) of reservoir. Using an electric submersible pump, the well has produced at stabilized rates of 1,524 bbls of oil per day (“bopd”) over 63 hours with 29.6-degree API gravity oil, a 5.6 % water cut, and a gas-oil ratio of 166 standard cubic feet per stock tank barrel. This is the second well in the Conejo discovery area.

Conejo A-1: The Conejo A-1 well continues to produce at a rate of 1,532 bopd over 192 hours with 26.8-degree API gravity oil, an 18 % water cut, and a gas-oil ratio of 277 standard cubic feet per stock tank barrel from the Basal Tena formation.

Colombia

Suroriente Block: The Raju well was spud on November 5, 2025, targeting the N Sand oil zone. The well discovered 21 ft of net reservoir with an average porosity of 17% in the N Sand formation. Currently the well is in early stages of testing and has confirmed the significant resource potential of the Cohembi field to the north extending the current development area by more than ~2 kilometers.

1 “Cash Flow” refers to line item “net cash provided by operating activities” under generally accepted accounting principles in the United States of America (“GAAP”).

2 “Free Cash Flow” is a non-GAAP measure and does not have a standardized meaning under GAAP. Free Cash Flow is defined as “net cash provided by operating activities” less capital expenditures. Refer to "Non-GAAP Measures" in this press release.

3 “Operating netback” is a non-GAAP measures and does not have standardized meaning under GAAP. Refer to “Non-GAAP Measures” in this press release.

4 Earnings before interest, taxes and depletion, depreciation and accretion (“EBITDA”) is a non-GAAP measure and does not have a standardized meaning under GAAP. Refer to "Non-GAAP Measures" in this press release.

5Gran Tierra’s current production is estimated as of December 9, 2025.

About Gran Tierra Energy Inc.

Presentation of Oil and Gas Information

This press release contains certain oil and gas metrics, including operating netback, which do not have standardized meanings or standard methods of calculation and therefore such measures may not be comparable to similar measures used by other companies and should not be used to make comparisons. Such metrics are calculated as described in this press release and have been included herein to provide readers with additional measures to evaluate the Company’s performance; however, such measures are not reliable indicators of the future performance of the Company and future performance may not compare to the performance in previous periods.

References to a formation where evidence of hydrocarbons has been encountered is not necessarily an indicator that hydrocarbons will be recoverable in commercial quantities or in any estimated volume. Gran Tierra's reported production, unless otherwise specified, is a mix of light crude oil and medium, heavy crude oil, tight oil, conventional natural gas, shale gas and natural gas liquids for which there is no precise breakdown since the Company’s sales volumes typically represent blends of more than one product type. Well test results should be considered as preliminary and not necessarily indicative of long-term performance or of ultimate recovery. Well log interpretations indicating oil and gas accumulations are not necessarily indicative of future production or ultimate recovery. If it is indicated that a pressure transient analysis or well-test interpretation has not been carried out, any data disclosed in that respect should be considered preliminary until such analysis has been completed. References to thickness of “oil pay” or of a formation where evidence of hydrocarbons has been encountered is not necessarily an indicator that hydrocarbons will be recoverable in commercial quantities or in any estimated volume.

Boe’s have been converted on the basis of six thousand cubic feet (“Mcf”) natural gas to 1 bbl of oil. Boe’s may be misleading, particularly if used in isolation. A boe conversion ratio of 6 Mcf: 1 bbl is based on an energy equivalency conversion method primarily applicable at the burner tip and does not represent a value equivalency at the wellhead. In addition, given that the value ratio based on the current price of oil as compared with natural gas is significantly different from the energy equivalent of six to one, utilizing a boe conversion ratio of 6 Mcf: 1 bbl would be misleading as an indication of value.

Non-GAAP Measures

Gran Tierra is unable to provide forward-looking net income, net cash provided by operating activities, and gross profit, the GAAP measures most directly comparable to the non-GAAP measures EBITDA, free cash flow and operating netback, respectively, due to the impracticality of quantifying certain components required by GAAP as a result of the inherent volatility in the value of certain financial instruments held by the Company and the inability to quantify the effectiveness of commodity price derivatives used to manage the variability in cash flows associated with the forecasted sale of its oil and natural gas production and changes in commodity prices.

Operating netback, as presented, is defined as gross profit less depletion and accretion related to producing assets. Management believes that operating netback is a useful supplemental measure for management and investors to analyze financial performance and provides an indication of the results generated by our principal business activities prior to the consideration of other income and expenses. Gran Tierra is unable to provide a quantitative reconciliation of forward-looking operating netback to its most directly comparable forward-looking GAAP measure because management cannot reliably predict certain of the necessary components of such forward-looking GAAP measures.

EBITDA as presented is defined as projected 2026 net income adjusted for DD&A expenses, interest expense and income tax expense or recovery. The most directly comparable GAAP measure is net income. Management uses this financial measure to analyze performance and income or loss generated by our principal business activities prior to the consideration of how non-cash items affect that income, and believes that this financial measure is also useful supplemental information for investors to analyze performance and our financial results. Gran Tierra is unable to provide a quantitative reconciliation of forward-looking EBITDA to its most directly comparable forward-looking GAAP measure because management cannot reliably predict certain of the necessary components of such forward-looking GAAP measure.

Free cash flow as presented is defined as GAAP projected “net cash provided by operating activities” less projected 2026 capital spending. The most directly comparable GAAP measure is net cash provided by operating activities. Management believes that free cash flow is a useful supplemental measure for management and investors to in order to evaluate the financial sustainability of the Company’s business. Gran Tierra is unable to provide a quantitative reconciliation of forward-looking free cash flow to its most directly comparable forward-looking GAAP measure because management cannot reliably predict certain of the necessary components of such forward-looking GAAP measure.