v3.22.2.2
Document and Entity Information
Jun. 30, 2022
Prospectus:  
Document Type 497
Document Period End Date Jun. 30, 2022
Entity Registrant Name MFS SERIES TRUST XVI
Entity Central Index Key 0000063067
Entity Inv Company Type N-1A
Amendment Flag false
Document Creation Date Dec. 08, 2022
Document Effective Date Dec. 08, 2022
Prospectus Date Oct. 24, 2022
MFS Prudent Investor Fund | A  
Prospectus:  
Trading Symbol FPPAX
MFS Prudent Investor Fund | B  
Prospectus:  
Trading Symbol FPPDX
MFS Prudent Investor Fund | C  
Prospectus:  
Trading Symbol FPPEX
MFS Prudent Investor Fund | I  
Prospectus:  
Trading Symbol FPPJX
MFS Prudent Investor Fund | R1  
Prospectus:  
Trading Symbol FPPRX
MFS Prudent Investor Fund | R2  
Prospectus:  
Trading Symbol FPPSX
MFS Prudent Investor Fund | R3  
Prospectus:  
Trading Symbol FPPQX
MFS Prudent Investor Fund | R4  
Prospectus:  
Trading Symbol FPPUX
MFS Prudent Investor Fund | R6  
Prospectus:  
Trading Symbol FPPVX