0000950156-06-000188 Sample Contracts

Exhibit 99.8(f) MASTER ADMINISTRATIVE SERVICES AGREEMENT dated this 1st day of March, 1997, as amended effective:

Master Administrative Services Agreement • May 17th, 2006 • MFS Series Trust Xiii • Massachusetts

• Contract Type
  Master Administrative Services Agreement
• Filed
  May 17th, 2006
• Company
  MFS Series Trust Xiii
• Jurisdiction
  Massachusetts

WITNESSETH:

Investment Advisory Agreement • May 17th, 2006 • MFS Series Trust Xiii

• Contract Type
  Investment Advisory Agreement
• Filed
  May 17th, 2006
• Company
  MFS Series Trust Xiii

WITNESSETH:

Sub-Advisory Agreement • May 17th, 2006 • MFS Series Trust Xiii • Massachusetts

• Contract Type
  Sub-Advisory Agreement
• Filed
  May 17th, 2006
• Company
  MFS Series Trust Xiii
• Jurisdiction
  Massachusetts

APPENDIX A

MFS Series Trust Xiii • May 17th, 2006

• Company
  MFS Series Trust Xiii
• Filed
  May 17th, 2006

The investment advisory fee payable by each Fund shall be computed and paid monthly at the annual rate equal to that Fund's average daily net assets for its then current fiscal year noted below: