Robert Stephenson, the engineer for the London and Birmingham Railway, originally planned that the line should pass through Leighton Buzzard. When the company sought to purchase the land, however, they met with opposition from Lady Lovat and Mr. Grant, two local inhabitants of some standing who had extensive interests in the Grand Junction Canal and viewed the potential railway as a serious competitor, though a public meeting in January 1831 was strongly in its favour. The railway was in fact built some distance to the west of Leighton Buzzard, and both the Ouzel and the Grand Junction Canal lay between it and the town. It was opened in 1838. The station was in Linslade and appears to have been known either as Linslade or Leighton Buzzard. It was the first station to serve Bedfordshire.

Leighton Buzzard in 1834 consisted of a township and hamlets containing 1,019 houses in which lived 5,159 people. By 1841 there were in the whole parish 1,168 occupied houses and 50 unoccupied ones, perhaps in process of construction. The population had risen to 6,053; of these 3,965 lived in the township, 2,965 of them having been born in the county and 1,040 outside it. This represents a considerable migration into Leighton, and the railway was probably one reason for it, though all towns were growing at this time.

Agriculture was important in the large parish of Leighton Buzzard, as in the similar one of Luton. In 1841 the tithable area was 2,270 acres; of this, over half, 1,208 acres, was arable, and nearly one-third, 700 acres, was meadow and pasture, near the Ouzel, suitable for cattle-rearing; the rest was commons and waste, approximately 170 acres. It is impossible to say exactly how the arable land was used; wheat, barley and oats were grown in considerable quantities, since the value of the tithes is given in terms of these crops. However, the details of the produce of Grove Bury farm are given, since tithes had to be paid on pigeons, milk, eggs, geese, pigs, calves, potatoes and turnips.

But Leighton Buzzard had also, even more than Luton, been a centre for the surrounding area, with a market since Saxon times and fairs, of which the first was granted in 1254.