There have been two Baronetcies created for members of the Spencer family.

The Baronetcy of Spencer of Yarnton was created on 29 June 1611 in the Baronetage of England for Thomas Spencer, Member of Parliament

Member of Parliament

A Member of Parliament is a representative of the voters to a :parliament. In many countries with bicameral parliaments, the term applies specifically to members of the lower house, as upper houses often have a different title, such as senate, and thus also have different titles for its members,...

 for Woodstock

Woodstock (UK Parliament constituency)

Woodstock, sometimes called New Woodstock, was a parliamentary constituency in the United Kingdom. It comprised the town of Woodstock in the county of Oxfordshire and the surrounding countryside and villages, and elected two Members of Parliament from its re-enfranchisement in 1553 until 1832...

 1604-11, son of Sir William Spencer, the third son of Sir John Spencer of Althorp

Althorp

Althorp is a country estate of about and a stately home in Northamptonshire, England. It is about north-west of the county town of Northampton. The late Diana, Princess of Wales is buried in the estate.-History:...

, Northamptonshire

Northamptonshire

Northamptonshire is a landlocked county in the English East Midlands, with a population of 629,676 as at the 2001 census. It has boundaries with the ceremonial counties of Warwickshire to the west, Leicestershire and Rutland to the north, Cambridgeshire to the east, Bedfordshire to the south-east,...

. The third Baronet also represented Woodstock 1660-1679. The Baronetcy was extinct on the death of the seventh Baronet a minor in 1741.

The Baronetcy of Spencer of Offley was created on 14 March 1627 for John Spencer of Offley Place, Great Offley, Hertfordshire

Hertfordshire

Hertfordshire is a ceremonial and non-metropolitan county in the East region of England. The county town is Hertford.The county is one of the Home Counties and lies inland, bordered by Greater London , Buckinghamshire , Bedfordshire , Cambridgeshire and...

, the son of Sir Richard Spencer, the fourth son of Sir John Spencer of Althorp. He died without male issue in 1633 and the Baronetcy was extinct, but was recreated on 26 September 1642 for his brother and heir Brocket Spencer. The fourth Baronet was Member of Parliament for Hertfordshire

Hertfordshire (UK Parliament constituency)

Hertfordshire was a county constituency covering the county of Hertfordshire in England. It returned two Knights of the Shire to the House of Commons of England until 1707, then to the House of Commons of Great Britain until 1800, and to the House of Commons of the Parliament of the United Kingdom...

 1705-08. On his death the Baronetcy was extinct. His estate was inherited by his four daughters, and ultimately by his greatgranddaughter who married Sir Thomas Salusbury

Spencer of Yarnton (1611)

• Sir Thomas Spencer, 1st Baronet  (1585–1622)
• Sir William Spencer, 2nd Baronet (1608–1647)
• Sir Thomas Spencer, 3rd Baronet
  Sir Thomas Spencer, 3rd Baronet
  Sir Thomas Spencer, 3rd Baronet was an English politician who sat in the House of Commons from 1660 to 1679.Spencer was the son of Sir William Spencer, 2nd Baronet and his wife Constance Lucy, daughter of Sir Thomas Lucy of Charlecote...
  
  (1639–1685)
• Sir Thomas Spencer, 4th Baronet (d 1722)
• Sir Henry Spencer, 5th Baronet (d 1726)
• Sir William Spencer, 6th Baronet (d 1735)
• Sir Charles Spencer, 7th Baronet (d 1741) Extinct on his death

Spencer of Offley (1642) Second creation

• Sir Brocket Spencer, 1st Baronet (1605–1668)
• Sir Richard Spencer, 2nd Baronet (1647–1688)
• Sir John Spencer, 3rd Baronet (1678–1699)
• Sir John Spencer, 4th Baronet (1650–1712) Extinct on his death