IN Brief:
- TrendForce forecasts global optical fibre demand of 577 million fibre-kilometres in 2026 and a supply shortfall of 180 million fibre-kilometres.
- Manufacturing capacity utilisation is estimated at 92%, with new optical preform production requiring approximately 18–24 months to establish.
- Spot quotations for selected optical fibre products are projected to reach approximately 2.8 to more than five times their 2025 levels.
TrendForce has forecast a global optical fibre supply shortfall of 180 million fibre-kilometres in 2026 as expanding data centre infrastructure and high-capacity telecommunications networks increase demand. The research group estimates that manufacturers are operating at approximately 92% capacity utilisation, while the time needed to expand production of optical fibre preforms is restricting the industry’s ability to increase output.
Its assessment, published on 19 October, estimates worldwide demand at 577 million fibre-kilometres during 2026 and expects supply constraints to persist until at least 2028. TrendForce says finished optical fibre spot quotations are rising substantially, with selected product categories projected to reach between approximately 2.8 and more than five times their 2025 price levels.
Fibre-kilometres measure the combined length of individual optical fibres, rather than the route distance covered by a cable installation. A cable containing multiple fibres contributes the length of each fibre to this measure. The reported shortage therefore describes fibre manufacturing requirements, not a prediction that 180 million kilometres of physical telecommunications routes will remain unbuilt.
Optical fibre carries information using modulated light transmitted through a carefully manufactured glass waveguide. A typical fibre consists of a central core surrounded by cladding, with their optical characteristics designed to confine and guide light along the fibre. Transmission performance depends on the fibre and the optical equipment connected to it, including the effects of attenuation, dispersion and the selected signalling technology.
The manufacturing process begins with an optical preform, a glass structure containing the material composition and refractive-index profile required for the finished fibre. The preform is heated in a drawing tower and stretched into a thin strand while the process controls its diameter, geometry and optical characteristics.
Protective coatings are applied during production to reduce the risk of mechanical damage and preserve the strength of the glass. The finished fibre is then tested before being incorporated into cable assemblies, where additional protective structures address the mechanical and environmental conditions of the intended installation.
Preform manufacture is a significant constraint in the current supply assessment. Producing suitable preforms requires specialist deposition equipment, controlled glass-processing operations and qualification of the resulting material. A change in material uniformity or the refractive-index profile can affect optical transmission characteristics, making manufacturing consistency important to the yield of the finished product.
TrendForce estimates that adding preform manufacturing capacity generally requires 18–24 months, including equipment installation and process establishment. Additional fibre drawing equipment cannot fully resolve a shortage if sufficient qualified preform material is unavailable. New capacity must also produce material that meets the optical and mechanical specifications required by customers.
With capacity utilisation estimated at 92%, manufacturers have limited spare output available within existing facilities. TrendForce also reports that inventory coverage has fallen from approximately four months in 2024 to one month, with some leading suppliers holding orders extending into the first quarter of 2027.
Those figures are market estimates and do not establish identical operating conditions for every manufacturer. Utilisation, order backlogs and inventory positions can vary between companies and fibre types, while additional production shifts or process improvements may affect output differently across individual factories.
Data centre construction is contributing to demand through internal cabling, links between facilities and the wider high-capacity networks connecting computing infrastructure. Optical links provide a way to transmit large quantities of information over distances and bandwidths that can make conventional copper connections less suitable for particular applications.
The required fibre depends on the network architecture. Shorter connections inside a facility may use different cabling and transceiver arrangements from long-distance backbone links, while data centre interconnects can involve demanding transmission capacities and network availability requirements. Cable routing, optical loss budgets, connector performance and installation practices affect the resulting system.
TrendForce estimates that data centre construction accounts for approximately 18–20% of global optical fibre demand in 2026. Its forecast suggests the proportion could rise to 30–35% in 2027 as additional facilities and supporting networks are developed. The figures represent estimated market shares, not completed purchases or confirmed future consumption.
Demand associated with AI infrastructure is not restricted to connections between processors inside computing equipment. Data centres require external connectivity to other facilities, telecommunications networks and customers, while larger deployments can increase the capacity required along regional and long-distance network routes.
Different optical fibre products are experiencing different pricing pressures. Bend-insensitive fibre, used where cabling has to accommodate comparatively tight installation geometries, is projected to command an average spot price exceeding five times its 2025 level during 2026.
Fibre used in data centre interconnects and high-capacity backbone networks is expected to reach approximately 2.8 times its earlier spot price, while mainstream telecommunications fibre quotations are projected to rise to around 3.7 times their 2025 levels. These are product-specific market estimates rather than a common price increase applicable to every fibre shipment.
The distinction between spot quotations and contracted supply is important. Large customers may purchase fibre through longer-term agreements with defined quantities, delivery periods and pricing arrangements. Their transaction prices can consequently differ from quotations available for smaller or immediate purchases.
TrendForce reports that telecommunications operators are increasingly seeking longer-term supply commitments. It cites a September 2026 agreement between Verizon and Corning covering approximately 129 million fibre-kilometres of optical fibre and connectivity products for delivery between 2027 and 2032.
That arrangement covers future deliveries under a separate commercial agreement and should not be treated as an allocation of fibre available to resolve the forecast 2026 shortfall. Its significance lies in the volume of material being secured over an extended period and the procurement planning required for major network programmes.
Optical fibre shortages can affect equipment deployment even when other parts of a communications system are available. Network construction depends on the coordinated supply of fibre, cables, connectors, optical transceivers, switches and installation services. A shortage of one required element can delay the commissioning of a link despite the availability of other components.
Conversely, an increase in optical fibre manufacturing capacity does not independently create additional operational network bandwidth. Installed fibre must be connected to suitable optical equipment, tested and integrated into a network architecture capable of delivering the required service.
TrendForce expects supply constraints to continue while manufacturers establish additional preform and drawing capacity. The outlook remains dependent on whether planned production investments proceed, the resulting manufacturing yields and the growth of data centre and telecommunications demand.
Changes in preform capacity, fibre inventories, order backlogs and contracted delivery periods will indicate whether supply is beginning to respond. TrendForce’s 2028 outlook remains a forecast, with the timing of any market recovery dependent on both manufacturing expansion and the rate at which network investment develops.
