The 18th Lord Berkley (created Baron Guterbock in 2000)
The 6th Lord Carrington (created Baron Carrington of Upton is 1999)
The 3rd Viscount Chandos (created Baron Lyttelton of Aldershot in
2000)
The 29th Earl of Crawford and Balcarres, K.T., G.C.V.O., D.L., P.C.
(created Baron Balniel in 1973 before inheriting the earldoms)
The 3rd Lord Grenfell (created Lord Grenfell of Kilvey in 2000)
The 14th Earl of Mar and Kellie, D.L. (created Baron Erskine of Alloa
Tower in 1999)
The 4th Lord Ponsonby of Shulbrede (created Baron Ponsonby of
Roehampton in 2000)
The 6th Lord Redesdale (created Lord Mitford in 2000)
The 1st Earl of Snowdon, G.C.V.O. (created Baron Armstrong-Jones in
1999)
The 3rd Lord Windlesham, C.V.O., P.C. (created Baron Hennessy in 1999)
The 7th Marquess of Salisbury, P.C. (created Baron Gascoyne-Cecil in
1999)
So the number is currently, by my count, at eleven. There are also 2
hereditary peeresses by marriage (Viscountess Halisham and Viscountess
Eccles) who sit with hereditary titles.
I wonder whether the current Lord Salisbury would have been awarded a
life peerage in 1999 had he not previously served as Leader of the
House, since he was called up by a writ of acceleration. Had he not
been first in line to a title, he would have, presumably, just been
give a regular old life peerage. Along the same lines, I wonder why a
writ of accelation was NOT used for the current Earl of Crawford, as
he was heir apparent to the title at that time.