Credit Facility Borrowing Base Redetermined to $215 Million

2021 Capital of $130-150 Million, Production of 28,000-30,000 BOPD, Cash Flow¹ of $150-170 Million

Resumption of Development Drilling at Acordionero Oil Field

CALGARY, Alberta, Dec. 07, 2020 (GLOBE NEWSWIRE) -- Gran Tierra Energy Inc. ("Gran Tierra" or the "Company") (NYSE American:GTE)(TSX:GTE)(LSE:GTE) today announced a financial update and the Company's 2021 capital budget and production guidance. 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 ("bbl") of oil per day ("bopd"), unless otherwise stated.

Key Highlights:

• Results of Semi-Annual Credit Facility Redetermination: The semi-annual redetermination of Gran Tierra's bank-syndicated revolving credit facility has been completed, and the syndicate of lenders party to the facility have agreed to amend the facility as follows:
  • The committed borrowing base under the credit facility has been redetermined to $215 million
  • $200 million will be readily available, with $15 million subject to the consent of the majority of lenders
  • The credit facility matures in November 2022
  • The Company expects the credit facility's balance to be approximately $185 million as of December 31, 2020
• Hedges In Place Designed To Protect Cash Flows: The Company has the following Brent oil price hedges in place:

Type of Instrument & Period	Volume (BOPD)	Sold Put ($/bbl)	Purchased Put ($/bbl)	Sold Call ($/bbl)	Premium ($/bbl)
3-Ways: October 1-December 31, 2020	11,000	27.05	35.68	43.43	0.54
3-Ways: January 1-June 30, 2021	14,000	36.43	45.14	51.45	0.21
Collars: January 1-June 30, 2021	1,000	n/a	45.00	50.40	n/a

• 2021 Guidance:
  • Gran Tierra is forecasting the following ranges for the Company's 2021 budget:

2021 Budget	Low Case	Base Case	High Case
Annual Average Brent Oil Price ($/bbl)	44.00	49.00	56.00
Total Company Production (bopd)	27,500-29,500	28,000-30,000	28,000-30,000
Operating Netback2 ($ million)	180-200	220-240	270-290
EBITDA2 ($ million)	165-185	200-220	240-260
Cash Flow1 ($ million)	115-135	150-170	190-210
Total Capital ($ million)	120-140	130-150	130-150
Bank Credit Facility Balance @ December 31, 2021 ($ million)	155-175	125-145	75-95
2021 Year-End Net Debt3 to Annualized Fourth Quarter 2021 EBITDA2	3.6-3.8	2.7-2.9	2.0-2.2
Number of Development Wells (gross)	12-16	14-18	14-18

2021 Capital Program: Gran Tierra plans to direct approximately 60% of the 2021 capital program toward continued development of the Acordionero field in the Middle Magdalena Valley Basin, another 35% toward development activities in the Putumayo Basin and the remaining 5% toward exploration-related activities throughout the Company's portfolio, in both Colombia and Ecuador

Fully Funded Capital Program: the Base Case 2021 capital budget of $130-150 million is expected to be fully funded from the Base Case 2021 cash flow¹ forecast of $150-170 million

Control of Capital Program: Gran Tierra has 100% working interest in and operatorship of the Company's major assets in Colombia and Ecuador; this full control gives the Company the flexibility to optimize its development and exploration programs with changes, either up or down, with oil prices

Debt Reduction: with 2021 expected free cash flow⁴ and changes in non-cash working capital (primarily related to the ongoing collection of tax receivables), Gran Tierra expects its credit facility to be paid down in the Base Case to a balance of $130-150 million by December 31, 2021

Gran Tierra expects approximate 2021 expenses and operating netback² per bbl⁵ to be in the following ranges:

2021 Budget	Low Case	Base Case	High Case
Brent Oil Price ($/bbl)	44.00	49.00	56.00
Expenses ($/bbl)
Transportation and Quality Discount	8.00-10.00	8.00-10.00	8.00-10.00
Royalties	3.00-4.00	5.00-6.00	7.00-8.00
Oil and Gas Sales Price ($/bbl)	30.00-32.00	34.00-36.00	38.00-40.00
Operating Costs	11.00-13.00	11.00-13.00	11.00-13.00
Transportation (Pipeline)	0.80-1.00	0.80-1.00	0.80-1.00
Operating Netback2 ($/bbl)5	17.00-19.00	21.00-23.00	26.00-28.00
General and Administrative	1.50-2.50	1.50-2.50	1.50-2.50
Interest and Financing	4.50-5.00	4.50-5.00	4.50-5.00
Taxes	0.00	0.00	0.00

• Acordionero Oil Field
  • Gran Tierra continues to workover offline oil wells to restore them to production with two workover rigs
  • The Company has also restarted development drilling at Acordionero by spudding the AC-64 oil well on November 30, 2020, from the newly constructed southwest pad; the Company has drilled to the planned total depth of AC-64, is currently running production casing in the well and plans to complete this well during December 2020
  • The drilling rig is then expected to drill the AC-65 oil well and the AC-66 water injection well in sequence during December 2020, Gran Tierra plans to finish the drilling of AC-65 before 2020 year-end and of AC-66 in January 2021
  • The plan is to begin the completion of AC-65 before 2020 year-end and to finish this work in January 2021, and to complete AC-66 in January 2021
  • The planned AC-64 and AC-65 oil wells are forecast to be brought on production during January 2021
  • The drilling rig is forecast to continue drilling new development wells at Acordionero throughout 2021; the next 10 planned wells (8 oil producers and 2 water injectors) are scheduled to be drilled from the new southwest pad
  • The planned new oil wells are each expected to have an initial oil production rate of approximately 550 BOPD (initial 30-day average rate), in line with the strong performance of wells drilled in the field during 2019 and first quarter 2020

Message to Shareholders

Gary Guidry, President and Chief Executive Officer of Gran Tierra, commented: "The safety of our staff, contractors and the local communities where we operate is always paramount. Our teams in Colombia, Canada and Ecuador have risen to meet the many challenges of 2020 through their diligent management of COVID-19 safety protocols. As a result, Gran Tierra has resumed development activities throughout our portfolio, including the ongoing well workover operations and the restart of development drilling at Acordionero.

Our teams' excellent work throughout 2020 has strongly positioned the Company for the resumption of prudent growth in 2021. We would also like to thank our bank lending syndicate for their ongoing support during these volatile times.

Our forecast 2021 capital budget is a balanced, returns-focused program which prioritizes free cash flow⁴ generation over the rate of development, exploration and production growth. With a keen focus of further strengthening our balance sheet, we plan to direct free cash flow⁴ to further debt reduction in 2021.

We see material upside in our exploration portfolio located in highly prospective geological trends in Colombia and Ecuador. For 2021, we have budgeted a measured 5% of our capital program to ongoing exploration-related activities, mostly directed at our large landholdings in the Putumayo Basin of Colombia and Oriente Basin of Ecuador.

Our 2021 plans are fully aligned with Gran Tierra's "Beyond Compliance Policy" which focuses on our commitments to environmental, social and governance ("ESG") excellence. Gran Tierra looks for significant opportunities and benefits to the environment or communities and voluntarily goes beyond what is legally required to protect the environment and provide social benefits because it is the right thing to do.

Gran Tierra has benefited from the continued support of the oil and gas industry by the governments of Colombia and Ecuador. In particular, the Colombian government has been supportive through expedited tax refunds, extensions on the timing to perform contractual commitments and during our resumption of workover and drilling activities and the reopening of suspended oil fields.

We believe we are well-positioned to navigate the current volatile environment with our low base decline, conventional oil asset base and the operational control for capital allocation and timing, while maintaining a low cost structure and the safety of our people."

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 "Operating netback" and earnings before interest, taxes and depletion, depreciation and accretion ("EBITDA") are non-GAAP measures and do not have a standardized meaning under GAAP. Refer to "Non-GAAP Measures" in this press release.
³ "Net debt" is a non-GAAP measure and does not have a standardized meaning under GAAP. Refer to "Non-GAAP Measures" in this press release.
⁴ "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 spending. Refer to "Non-GAAP Measures" in this press release.
⁵ "Operating netback per bbl" is a non-GAAP measure and does not have a standardized meaning under GAAP. Refer to "Non-GAAP Measures" in this press release.

Contact Information

For investor and media inquiries please contact:

Gary Guidry
President & Chief Executive Officer

Ryan Ellson
Executive Vice President & Chief Financial Officer

Rodger Trimble
Vice President, Investor Relations

+1-403-265-3221

[email protected]

About Gran Tierra Energy Inc.

Gran Tierra Energy Inc. together with its subsidiaries is an independent international energy company focused on oil and natural gas exploration and production in Colombia and Ecuador. The Company is focused on its existing portfolio of assets in Colombia and Ecuador and will pursue new growth opportunities throughout Colombia and Latin America, leveraging our financial strength. The Company's common stock trades on the NYSE American, the Toronto Stock Exchange and the London Stock Exchange under the ticker symbol GTE. Additional information concerning Gran Tierra is available at www.grantierra.com. Information on the Company's website does not constitute a part of this press release. Investor inquiries may be directed to [email protected] or (403) 265-3221.

Gran Tierra's Securities and Exchange Commission filings are available on the SEC website at http://www.sec.gov and on SEDAR at http://www.sedar.com and UK regulatory filings are available on the National Storage Mechanism website at https://data.fca.org.uk/#/nsm/nationalstoragemechanism.

Forward-Looking Statements and Legal Advisories:

This press release contains opinions, forecasts, projections, and other statements about future events or results that constitute forward-looking statements within the meaning of the United States Private Securities Litigation Reform Act of 1995, Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended, and financial outlook and forward looking information within the meaning of applicable Canadian securities laws (collectively, "forward-looking statements"). All statements other than statements of historical facts included in this press release regarding our financial position, business strategy, plans and objectives for future operations, capital spending plans, leverage, results of operations and those statements preceded by, followed by or that otherwise include the words "believe", "expect", "intend", "anticipate", "forecast", "budget", "will", "estimate", "target", "project", "goal", "plan", "should", "guidance" or similar expressions are forward-looking statements. Such forward-looking statements include, but are not limited to, the Company's capital budget amount and uses, funds available under our credit facility, ability of hedges to protect cash flows, drilling and capital program, including the changes thereto, along with the allocation of the Company's capital budget to development, exploration and drilling activities, trends, infrastructure schedules and the expected timing and drilling sequence of certain projects; the Company's operations; expected future net cash provided by operating activities (described in this press release as "cash flow"), free cash flow, operating netback, EBITDA, net debt and certain associated metrics; our strategy regarding debt reduction; expected cost savings; anticipated capital expenditures, including the location and impact of capital expenditures; timing and ability to pay down the credit facility; our business strategies; our ability to grow in both the near and long term and the funding of our growth opportunities; the plans, objectives, expectations and intentions of the Company regarding production, exploration, development; ESG-related efforts and impacts; and the future development of the Company's business. The forward-looking statements contained in this press release reflect several material factors and expectations and assumptions of Gran Tierra including, without limitation, that Gran Tierra will continue to conduct its operations in a manner consistent with its current expectations, the accuracy of testing and production results and seismic data, pricing and cost estimates (including with respect to commodity pricing and exchange rates), rig availability, the extent and effect of delivery disruptions and the general continuance of current or, where applicable, assumed operational, regulatory and industry conditions including in areas of potential expansion, the receipt of approval from the government authorities and the ability of Gran Tierra to execute its current business and operational plans in the manner currently planned. Gran Tierra believes the material factors, expectations and assumptions reflected in the forward-looking statements are reasonable at this time but no assurance can be given that these factors, expectations and assumptions will prove to be correct.

Among the important factors that could cause actual results to differ materially from those indicated by the forward-looking statements in this press release are: sustained or future declines in commodity prices and potential resulting future impairments; Gran Tierra's operations are located in South America, and unexpected problems can arise due to guerrilla activity; technical difficulties and operational difficulties may arise which impact the production, transport or sale of our products; global health (including the ongoing COVID-19 pandemic), geographic, political and weather conditions can impact the production, transport or sale of our products; the risk that current global economic and credit conditions may impact oil prices and oil consumption more than Gran Tierra currently predicts; the ability of Gran Tierra to execute its business plan; the risk that unexpected delays and difficulties in developing currently -owned properties may occur; the timely receipt of regulatory or other required approvals for our operating activities; unexpected delays due to the limited availability of drilling equipment and personnel; the risk that oil prices could continue to decline or be volatile, or current global economic and credit market conditions may impact current oil prices or expectations regarding future oil prices and oil consumption or limit access to capital, which could cause Gran Tierra to further modify its strategy and capital spending program; and the risk factors detailed from time to time in Gran Tierra's periodic reports filed with the Securities and Exchange Commission, including, without limitation, under the caption "Risk Factors" in Gran Tierra's Quarterly Report for the quarter ended September 30, 2020 and Annual Report on Form 10-K for the year ended December 31, 2019 and its other filings with the SEC. These filings are available on the SEC website at http://www.sec.gov and on SEDAR at http://www.sedar.com. Although the current guidance, capital spending program and long term strategy of Gran Tierra are based upon the current expectations of the management of Gran Tierra, should any one of a number of issues arise, Gran Tierra may find it necessary to alter its business strategy and/or capital spending program and there can be no assurance as at the date of this press release as to how those funds may be reallocated or strategy changed and how that would impact Gran Tierra's results of operations and financing position.

All forward-looking statements are made as of the date of this press release and the fact that this press release remains available does not constitute a representation by Gran Tierra that the Company believes these forward-looking statements continue to be true as of any subsequent date. Actual results may vary materially from the expected results expressed in forward-looking statements. Gran Tierra disclaims any intention or obligation to update or revise any forward-looking statements, whether as a result of new information, future events or otherwise, except as expressly required by applicable securities laws. Gran Tierra's forward-looking statements are expressly qualified in their entirety by this cautionary statement.

The estimates of future production, EBITDA, net cash provided by operating activities (described in this press release as "cash flow"), free cash flow, operating netback, net debt, total capital and certain expenses or costs may be considered to be future-oriented financial information or a financial outlook for the purposes of applicable Canadian securities laws. Financial outlook and future-oriented financial information contained in this press release about prospective financial performance, financial position or cash flows are provided to give the reader a better understanding of the potential future performance of the Company in certain areas and are based on assumptions about future events, including economic conditions and proposed courses of action, based on management's assessment of the relevant information currently available, and to become available in the future. In particular, this press release contains projected operational and financial information for 2021 and development activity expectations for 2022. These projections contain forward-looking statements and are based on a number of material assumptions and factors, including those set out above. Actual results may differ significantly from the projections presented herein. The actual results of Gran Tierra's operations for any period could vary from the amounts set forth in these projections, and such variations may be material. See above for a discussion of the risks that could cause actual results to vary. The future-oriented financial information and financial outlooks contained in this press release have been approved by management as of the date of this press release. Readers are cautioned that any such financial outlook and future-oriented financial and operational information contained herein should not be used for purposes other than those for which it is disclosed herein. The Company and its management believe that the prospective financial information has been prepared on a reasonable basis, reflecting management's best estimates and judgments, and represent, to the best of management's knowledge and opinion, the Company's expected course of action. However, because this information is highly subjective, it should not be relied on as necessarily indicative of future results.

Oil and Gas Disclaimer

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. These metrics are calculated as described in this press release and management believes that they are useful supplemental measures for investors. Such metrics 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 is a mix of light crude oil and medium and heavy crude oil for which there is not a precise breakdown since the Company's oil sales volumes typically represent blends of more than one type of crude oil. 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.

Non-GAAP Measures

This press release includes forward-looking non-GAAP financial measures as further described herein. These non-GAAP measures do not have a standardized meaning under GAAP. Investors are cautioned that these measures should not be construed as an alternative to net income or loss or other measures of financial performance as determined in accordance with GAAP. Gran Tierra's method of calculating these measures may differ from other companies and, accordingly, it may not be comparable to similar measures used by other companies. These non-GAAP financial measures are presented along with the corresponding GAAP measure so as to not imply that more emphasis should be placed on the non-GAAP measure.

Gran Tierra is unable to provide forward-looking net income and oil and gas sales, the GAAP measures most directly comparable to the non-GAAP measures EBITDA 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 production and changes in commodity prices.

Operating netback as presented is defined as projected 2021 oil and gas sales less projected 2021 operating and transportation expenses. Operating netback per bbl as presented is defined as projected oil and gas sales price less 2021 forecasts of transportation and quality discount, royalties, operating costs and pipeline transportation from the 2021 budget Brent oil price forecast as outlined in the table above. The most directly comparable GAAP measures are oil and gas sales and oil and gas sales price, respectively. Management believes that operating netback and operating netback per bbl are useful supplemental measures 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 either forward-looking operating netback or operating netback per bbl 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 2021 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 2021 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.

Net Debt as presented is defined as projected working capital at December 31, 2021, less $600 million in senior notes and borrowings under the credit facility. Management believes that net debt is a useful supplemental measure for management and investors to in order to evaluate the financial sustainability of the Company's business and leverage. The most directly comparable GAAP measure is total debt. Gran Tierra is unable to provide a quantitative reconciliation of forward-looking net debt 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.