Telesat (TSAT) adds 500 MHz military Ka-band to Lightspeed LEO network

Rhea-AI Filing Summary

Telesat Corporation is updating its Telesat Lightspeed low Earth orbit satellite network to add 500 MHz of military Ka-band (Mil-Ka) spectrum to the initial 156 satellites. This change targets fast-growing demand from allied defence users for secure, resilient, low-latency communications.

The Mil-Ka spectrum is immediately adjacent to Lightspeed’s commercial Ka-band, so it can be integrated without affecting the deployment schedule and with only a modest increase in program cost. The Mil-Ka capacity will replace an equivalent amount of commercial Ka-band on the user link, leaving gateway links unchanged.

Telesat expects this enhancement to materially increase the global supply of Mil-Ka capacity and to offer performance that compares favorably with traditional geostationary Mil-Ka systems. The first two Lightspeed production satellites are scheduled to launch in December 2026, followed by a high launch cadence through 2027, supporting global, interoperable services for coalition defence and sovereignty missions.

Insights

Satellite communications and defense markets analyst

Telesat shifts Lightspeed toward defence users with added Mil-Ka capacity.

Telesat is reallocating 500 MHz of spectrum on its Lightspeed LEO constellation from commercial Ka-band to military Ka-band. Because Mil-Ka sits adjacent to its commercial band, the company can implement this without delaying deployment and with only modest additional cost.

This move targets rising demand from NATO and allied governments for resilient, low-latency LEO connectivity that complements legacy geostationary Mil-Ka systems. It also positions Lightspeed more squarely in the defence and sovereignty market, where procurement cycles are long but contracts can be sizable and sticky.

The first two Lightspeed production satellites are slated for launch in December 2026, with a high launch cadence through 2027. Future disclosures about funding progress, defence customer commitments, and constellation deployment milestones will be important to understand how this strategic refocus translates into revenue and utilization.

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

FORM 6-K

Report of Foreign Private Issuer Pursuant to Rule 13a-16 or 15d-16
Under the Securities Exchange Act of 1934

For the Month of March 2026

Commission File No.: 001-41083

TELESAT CORPORATION
(Name of Registrant)

160 Elgin Street, Suite 2100, Ottawa, Ontario, Canada K2P 2P7
(Address of Principal Executive Office)

Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F.

Form 20-F ☒            Form 40-F ☐

EXHIBITS

The following information is furnished to the Securities and Exchange Commission as part of this report on Form 6-K:

Exhibit No.		Document
99.1		Press Release dated March 17, 2026 – “Telesat adds military Ka-band to Telesat Lightspeed to meet strong global demand for defence and sovereignty requirements”

1

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

	TELESAT CORPORATION
Date: March 17, 2026	By:	/s/ CHRISTOPHER S. DIFRANCESCO
	Name:	Christopher S. DiFrancesco
	Title:	Vice President, General Counsel and Secretary

2

Exhibit 99.1

Telesat adds military Ka-band to Telesat Lightspeed to meet strong global demand for defence and sovereignty requirements

Telesat Lightspeed will significantly increase and improve the global military Ka-band satellite capability available to allied defence users

OTTAWA, CANADA – March 17, 2026 – Telesat (Nasdaq and TSX: TSAT), one of the world’s largest and most innovative satellite operators, today announced it is adding 500 MHz of military Ka-band (Mil-Ka) spectrum to the initial 156 satellites in the Telesat Lightspeed constellation to meet the fast-growing global requirements of allied defence users. Mil-Ka is immediately adjacent to the commercial Ka-band spectrum used by Telesat Lightspeed, which allows the change to be made without adversely impacting schedule and with only a modest impact on program cost. The 500 MHz of Mil-Ka will replace the same amount of commercial Ka-band spectrum on the network’s user link, with the gateway link being unaffected by the spectrum change.

Governments have long relied on geostationary (GEO) Mil-Ka systems to meet their most mission critical satellite communications requirements. More recently, and as a result of evolving operational requirements, advances in technology, and a significant increase in defence spending by NATO members and other allied governments, military planners are advancing satellite communications programs that leverage the advantages of distributed, resilient, high throughput, low-latency LEO networks. Telesat Lightspeed was designed from inception to meet the security and resiliency requirements of defence organizations, and the addition of interoperable Mil-Ka connectivity further enhances its ability to support rapidly expanding defence and sovereignty requirements.

“We’re seeing very significant global demand for a Mil-Ka LEO satellite capability as governments respond to recent geopolitical developments and recognize the clear operational advantages offered by advanced LEO constellations,” stated Dan Goldberg, Telesat’s President and CEO. “The addition of Mil-Ka to Telesat Lightspeed will result in a substantial increase to the current global supply of Mil-Ka capacity. Moreover, by integrating it with the already highly advanced Telesat Lightspeed network, the Telesat Mil-Ka capability is expected to have meaningfully superior performance characteristics relative to the Mil-Ka platforms that allied governments have historically relied upon. This is an important development and one that underscores Telesat’s decades-long commitment to support the mission critical requirements of allied defence users.”

Military satcom architectures require interoperability across national networks, enabling coalition partners to integrate capabilities, share mission-critical connectivity, and maintain assured communications under joint operational command. With persistent global coverage - including over the Arctic - Telesat Lightspeed Mil-Ka services add a powerful, dedicated layer of interoperable capacity through a secure, flexible, and highly robust data transport layer.

The first two Telesat Lightspeed production satellites will be launched in December 2026, followed by a high cadence launch schedule throughout 2027.

About Telesat

Backed by a legacy of engineering excellence, reliability and industry-leading customer service, Telesat (Nasdaq and TSX: TSAT) is one of the largest and most innovative global satellite operators. Telesat works collaboratively with its customers to deliver critical connectivity solutions that tackle the world’s most complex communications challenges, providing powerful advantages that improve their operations and drive profitable growth.

Continuously innovating to meet the connectivity demands of the future, Telesat Lightspeed, the company’s state-of-the-art Low Earth Orbit (LEO) satellite network, has been optimized to meet the rigorous requirements of telecom, government, maritime and aeronautical customers. Telesat Lightspeed will redefine global satellite connectivity with ubiquitous, affordable, high-capacity, secure and resilient links with fibre-like speeds. For updates on Telesat, follow us on LinkedIn, X, or visit www.telesat.com.

Media Contact:

W2 Communications for Telesat

telesat@w2comm.com

Telesat Forward-Looking Statements Safe Harbor

This news release contains statements that are not based on historical fact and are “forward-looking statements’’ and “forward looking information” within the meaning of the Private Securities Litigation Reform Act of 1995 and Canadian securities laws. When used herein, statements which are not historical in nature, or which contain the words “will,” “expected,” or similar expressions, are forward-looking statements. In addition, Telesat or its representatives have made or may make forward-looking statements, provide forward looking information, orally or in writing, which may be included in, but are not limited to, various filings made from time to time with the U.S. Securities and Exchange Commission (“SEC”) and Canadian securities regulatory authorities, and news releases or oral statements made with the approval of an authorized executive officer of Telesat. All statements made in this news release are made only as of the date set forth at the beginning of this news release. Telesat undertakes no obligation to update the statements made in this news release in the event facts or circumstances subsequently change after the date of this news release.

These forward-looking statements and this forward looking information are not guarantees of future performance, are based on Telesat’s current expectations, and are subject to a number of known and unknown risks, uncertainties assumptions, and other factors, some of which are beyond Telesat’s control, are difficult to predict, and could cause actual results to differ materially from those expressed, forecasted or implied in the forward-looking statements and forward looking information.

Known risks and uncertainties include but are not limited to: risks associated with financial factors, including swings in the global financial markets, access to capital to construct our LEO satellite constellation and refinance our GEO debt, volatility of securities values in an industry sector where values may be influenced by economic and other factors beyond Telesat’s control, inflation, rising or prolonged elevated interest rates, fluctuations in foreign exchange rates, and tariffs; risks associated with operating satellites and providing satellite services, including satellite construction or launch delays, launch failures, in-orbit failures, impaired satellite performance or dependence on large customers; the ability to deploy successfully an advanced global LEO satellite constellation and the timing of any such deployment; Telesat’s ability to meet the conditions for advance of the loans under the funding agreements for the constellation; technological hurdles, including Telesat’s and Telesat’s contractors’ development and deployment of the new technologies required to complete the constellation in time to meet Telesat’s schedule, or at all; the availability of services and components from Telesat’s and Telesat’s contractors’ supply chains; competition, including with other LEO systems, deployed and yet to be deployed; risks associated with domestic and foreign government regulation, including government restrictions and regulations, access to sufficient orbital spectrum to be able to deliver services effectively and access to sufficient geographic markets in which to sell those services; Telesat’s ability to develop significant commercial and operational capabilities; and the ability to expand Telesat’s existing satellite utilization. The foregoing list of important factors is not exhaustive. Investors should review the other risk factors discussed in Telesat Corporation’s annual report on Form 20-F for the year ended December 31, 2025 that was filed on March 17, 2026 with the SEC and the Canadian securities regulatory authorities at the System for Electronic Document Analysis and Retrieval+ (“SEDAR+”), and may be accessed on the SEC’s website at www.sec.gov and SEDAR+’s website at www.sedarplus.ca.

FAQ

What change did Telesat (TSAT) announce for its Lightspeed constellation?

Telesat is adding 500 MHz of military Ka-band spectrum to the initial 156 Telesat Lightspeed satellites. This replaces an equivalent amount of commercial Ka-band on the user link, aiming to better serve allied defence and sovereignty communication requirements worldwide.

Why is Telesat adding military Ka-band to Telesat Lightspeed?

Telesat cites very strong global demand from allied defence users for low Earth orbit Mil-Ka capability. Governments want secure, resilient, low-latency networks to complement traditional geostationary systems as defence spending, operational requirements, and technology expectations increase.

Will adding Mil-Ka spectrum delay the Telesat Lightspeed deployment?

Telesat states the Mil-Ka band sits immediately adjacent to its commercial Ka-band, so the modification should not adversely impact the deployment schedule. The company characterizes the change as having only a modest impact on overall program cost while preserving launch timing.

How does the Mil-Ka upgrade affect Telesat Lightspeed’s commercial Ka-band capacity?

The 500 MHz of military Ka-band will replace the same amount of commercial Ka-band spectrum on the network’s user link. Telesat indicates that the gateway link architecture remains unaffected, while the change reallocates capacity toward dedicated military and sovereignty services.

When will Telesat Lightspeed Mil-Ka services begin launching?

Telesat expects to launch the first two Telesat Lightspeed production satellites in December 2026. A high launch cadence is planned throughout 2027, which should progressively bring the Mil-Ka-enabled constellation into service for global defence and sovereignty users.

What benefits does Telesat claim for its Mil-Ka LEO services versus existing systems?

Telesat expects its Mil-Ka capability to substantially increase global Mil-Ka supply and to offer superior performance relative to traditional geostationary platforms. The company highlights distributed, resilient, high-throughput, low-latency connectivity and interoperable coverage, including persistent service over the Arctic regions.

Filing Exhibits & Attachments

1 document

Press Releases

• EX-99.1 PRESS RELEASE DATED MARCH 17, 2026 - "TELESAT ADDS MILITARY KA-BAND TO TELESAT L 14.0 KB