Morningstar

MFS Core Bond Fund I MCBFX

Medalist Rating as of Aug 31, 2026 See MFS Investment Hub

Will MCBFX outperform in the future?

Get our overall rating based on a fundamental assessment of the pillars below.

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Process Pillar

The Process Pillar is our assessment of how sensible, clearly defined, and repeatable MCBFX’s performance objective and investment process is for both security selection and portfolio construction.
People Pillar

The People Pillar is our evaluation of the MCBFX management team’s experience and ability. We find that high-quality management teams deliver superior performance relative to their benchmarks and/or peers.
Parent Pillar

The Parent Pillar is our rating of MCBFX’s parent organization’s priorities and whether they’re in line with investors’ interests.

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Morningstar Automated Analysis

Summary

MFS Core Bond I holds a quantitatively derived Gold Morningstar Medalist Rating. The rating reflects that it has scored particularly well on factors Morningstar research associates with future outperformance relative to category peers.

by Morningstar Automated Analysis

Rated on Aug 31, 2026 Published on Sep 29, 2026

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