He studied art at Middlesbrough College of Art from 1956-9, moving south to London in the 1960s to study at the Slade School of Art. It was there he encountered William Coldstream and Anthony Gross, among others. Following his time at the Slade, Tillyer took up a French Government Scholarship to study gravure under Stanley William Hayter, at Atelier 17 in Paris.
On his return to London, Tillyer began to make radically experimental work which raised questions about the relationship of art to the world - man to nature. Wandering between the conceptual intrigue of works like Eight Clouds and the Minimalist assertions of works like Red Interior, Tillyer developed a range of means by which to deepen the external references of his work.
Consistently searching for new means by which to explore his thoughts, the 1970s saw Tillyer return to print-making with renewed vigour. He won international acclaim at the Second International Print Bienalle in Kraków, and found the support of Bernard Jacobson, who has been his dealer ever since. With these prints Tillyer used a variety of techniques, from etching to five tone screenprinting, to create lattices, which through the gradation of tone themselves depicted what Pat Gilmour, the head of the Print Department at the Tate, described as 'a cool and unpeopled world...in which to reflect the surrounding flux of nature'.
Such concerns have continued to underpin Tillyer's practice to the present day, the artist balancing formal and technical experimentation against the demands of subject matter - demanding multiple reactions from the viewer. His most recent series reveals the artist returning to some of the earliest themes of his career, isolating John Constable's cloud studies, as a motif through which to explore his own thoughts about the English Landscape today.
In 2010 a major monograph on his watercolours was published by 21 Publishing covering almost 40 years of his practise. In the extensive text American art critic and poet John Yau writes "However beautiful they are, and many of them are extremely beautiful, almost painfully so, Tillyer's watercolours never lead us away in favour of an Edenic vision"
In 2013 Mima Middlesbrough Institute of Modern Art in Middlesbrough gave Tillyer his first major retrospective exhibition since 1996.
- Norbert Lynton, William Tillyer: Against the Grain, 2000, 21 Publishing Ltd. London
- Pat Gilmour, 'A Furnished Landscape', Bernard Jacobson Gallery, 1974
- Mel Gooding, William Tillyer 1956-1996, The Cleveland Gallery, Middlesbrough, 1996
- John Yau, William Tillyer: Watercolours, 21 Publishing, London, 2010
- Gilmour, Pat (1974). William Tillyer: A Furnished Landscape. Bernard Jacobson Ltd.
- Wiedel-Kaufmann, Ben (2010). William Tillyer: New Paintings: Clouds. Bernard Jacobson Gallery, London. ISBN 978-1-872784-42-7.