By Robb M. Stewart

OTTAWA--A further jump in Canadian exports to a record high widened the country's trade surplus with the world to the largest in four years, buoyed by a fourth straight month of increased shipments to the U.S.

Canada recorded a merchandise-trade surplus 4.24 billion Canadian dollars, the equivalent of about US$2.99 billion, Statistics Canada said Tuesday.

Canada has now racked up trade surpluses three months running as exports have rebounded following a weak start to the year and energy prices spiked with the conflict in the Middle East. Economists were expecting a C$2.68 billion surfeit in the latest month following April's upwardly revised C$3.41 surplus.

The value of Canadian goods exports rose a fourth consecutive month, climbing 0.9% between April and May to C$77.1 billion, while the value of goods coming into the country dipped 0.2% to C$72.86 billion, the national data agency said.

Shipments to the U.S. were up 1.5% for the month, more than offsetting a 0.3% slide in exports to all other countries. Imports from Canada's neighbor fell 1.4%, while imports from non-U.S. countries rose 1.5%.

That saw Canada's longstanding surplus with the U.S. expand to C$11.63 billion, the largest since the record seen in January 2025, while the trade deficit with countries other than the U.S. widened by C$519 million month-over-month to C$7.38 billion.

Exports increased broadly in May, with the largest rise recorded in shipments of metal ores and non-metallic minerals, driven by a surge in sulfur exports as global supplies were constricted by the Iran war and the squeeze on goods moving through the Strait of Hormuz. Canadian exports of gold also increased during the month, as did shipments of unwrought aluminum and aluminum alloys, which increased to the most in for years with exports to the Netherlands, Italy and Greece.

Exports of energy products slipped 2% from the month before with an estimated drop in crude oil volumes, but were about 70% higher than a year earlier. The softening in May following a sharp increase in energy exports in April was moderated by higher shipments of nuclear fuel, natural gas and refined petroleum products. Excluding energy products, overall exports for the month were up 2% from April.

On the import side, inbound goods pulled back from the record high level in April, largely due to a decline in metals and minerals and a drop in gold purchases. Imports of consumer goods rose in May, driven by batteries and battery chargers from China, and imports of pharmaceutical and medicinal products rose, mainly coming in from Germany, the U.S. and Spain.

In volume terms, exports were essentially unchanged and imports rose a modest 0.4%.

When international trade in goods and international trade in services were combined, Canadian exports increased 0.9%, while imports rose 0.3%. As a result, Canada's trade surplus incorporating both goods and services widened to C$3.78 billion from C$3.17 billion in April.

Write to Robb M. Stewart at robb.stewart@wsj.com