# MFS Cash Reserve Fund — new fund registration

MFS SERIES TRUST I registered fund series on Form 485APOS, filed 2006-10-27. Featured series: MFS Cash Reserve Fund.

## Registration

- Registrant / trust: MFS SERIES TRUST I
- CIK: 0000798244
- Form: 485APOS
- Filed: 2006-10-27
- State of incorporation: MA
- Accession: 0000950156-06-000535

## Series & classes (96)

_Showing 25 of 96 series/class rows._

| Series | Class | Ticker | New |
| --- | --- | --- | --- |
| [MFS Cash Reserve Fund](https://search.stillhousedata.com/fund/S000000762) | A | MSRXX | — |
| [MFS Cash Reserve Fund](https://search.stillhousedata.com/fund/S000000762) | 529B | — | — |
| [MFS Cash Reserve Fund](https://search.stillhousedata.com/fund/S000000762) | 529C | — | — |
| [MFS Cash Reserve Fund](https://search.stillhousedata.com/fund/S000000762) | B | MCRXX | — |
| [MFS Cash Reserve Fund](https://search.stillhousedata.com/fund/S000000762) | C | MCCXX | — |
| [MFS Cash Reserve Fund](https://search.stillhousedata.com/fund/S000000762) | R1 | CRVXX | — |
| [MFS Cash Reserve Fund](https://search.stillhousedata.com/fund/S000000762) | R2 | — | — |
| [MFS Cash Reserve Fund](https://search.stillhousedata.com/fund/S000000762) | R3 | CRMXX | — |
| [MFS Cash Reserve Fund](https://search.stillhousedata.com/fund/S000000762) | R4 | CRJXX | — |
| [MFS Cash Reserve Fund](https://search.stillhousedata.com/fund/S000000762) | R5 | CRKXX | — |
| [MFS Cash Reserve Fund](https://search.stillhousedata.com/fund/S000000762) | 529A | — | — |
| [MFS Core Equity Fund](https://search.stillhousedata.com/fund/S000000763) | A | MRGAX | — |
| [MFS Core Equity Fund](https://search.stillhousedata.com/fund/S000000763) | R5 | MRGJX | — |
| [MFS Core Equity Fund](https://search.stillhousedata.com/fund/S000000763) | B | MRGBX | — |
| [MFS Core Equity Fund](https://search.stillhousedata.com/fund/S000000763) | C | MRGCX | — |
| [MFS Core Equity Fund](https://search.stillhousedata.com/fund/S000000763) | I | MRGRX | — |
| [MFS Core Equity Fund](https://search.stillhousedata.com/fund/S000000763) | R | MGIRX | — |
| [MFS Core Equity Fund](https://search.stillhousedata.com/fund/S000000763) | R1 | MRGGX | — |
| [MFS Core Equity Fund](https://search.stillhousedata.com/fund/S000000763) | R2 | MRGKX | — |
| [MFS Core Equity Fund](https://search.stillhousedata.com/fund/S000000763) | R3 | MRERX | — |
| [MFS Core Equity Fund](https://search.stillhousedata.com/fund/S000000763) | R4 | MRGHX | — |
| [MFS Core Growth Fund](https://search.stillhousedata.com/fund/S000000764) | A | MFCAX | — |
| [MFS Core Growth Fund](https://search.stillhousedata.com/fund/S000000764) | R5 | MFCJX | — |
| [MFS Core Growth Fund](https://search.stillhousedata.com/fund/S000000764) | B | MFCBX | — |
| [MFS Core Growth Fund](https://search.stillhousedata.com/fund/S000000764) | C | MFCCX | — |

## Fees (from the effective prospectus)

- 12b-1 fee: 0.25%
- Gross expense ratio: 0.83%
- Management fee: 0.40%
- Net expense ratio: 0.45%
- Other expenses: 0.18%

## Investment objective

The funds investment objective is to seek current income consistent with preservation of capital and liquidity.

## Advisers

- [Massachusetts Financial Services Company (Advisor)](https://search.stillhousedata.com/firm/110045)

## Other filings by this registrant (10)

- [485APOS — 2025-10-08](https://search.stillhousedata.com/launch/0000912938-25-000192)
- [485APOS — 2016-10-27](https://search.stillhousedata.com/launch/0001104659-16-152442)
- [485APOS — 2015-10-29](https://search.stillhousedata.com/launch/0001104659-15-073931)
- [485APOS — 2014-10-29](https://search.stillhousedata.com/launch/0001104659-14-074634)
- [485APOS — 2013-08-09 (18 new series)](https://search.stillhousedata.com/launch/0001104659-13-062108)
- [485APOS — 2011-06-30 (4 new series)](https://search.stillhousedata.com/launch/0001104659-11-037267)
- [485APOS — 2009-10-13](https://search.stillhousedata.com/launch/0001193125-09-206890)
- [485APOS — 2007-01-29](https://search.stillhousedata.com/launch/0000950156-07-000058)
- [485APOS — 2006-02-24](https://search.stillhousedata.com/launch/0000950156-06-000045)
- [485APOS — 2004-10-29](https://search.stillhousedata.com/launch/0000950156-04-000241)

## More

- [Registrant profile: MFS SERIES TRUST I](https://search.stillhousedata.com/registrant/798244)
- [This page as markdown (for LLM agents)](https://search.stillhousedata.com/launch/0000950156-06-000535.md)
- [Search all SEC filings, advisers and people on Adviser Search](https://search.stillhousedata.com/)

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Source: public SEC filing data via Adviser Search (https://search.stillhousedata.com).
Agents: this data is also queryable via MCP tools and read-only SQL — see https://search.stillhousedata.com/llms.txt.