According to a BBC report:
“A survey has found that only 10% of politicians conduct a quarter or more of their correspondence via e-mail.
The vast majority still prefer to use post and many respond to electronic messages with a written letter the survey also showed.
Only one of the MPs questioned used e-mail for more than 75% of their correspondence.”
It turns out that all of them have email addresses now, but some have actually switched theirs off.