At Cromwell, We Love Taxes. (weird, right?)

We are a family business that has provided tax and bookkeeping services to Sonoma County for three generations.

Our Team

Madelyne Cromwell owner of Cromwell Tax & Bookkeeping

Madelyne Cromwell, E.A.

Madelyne Cromwell, an Enrolled Agent and owner of Cromwell Tax & Bookkeeping, specializes in tax preparation, planning, and bookkeeping. With authorization to represent clients before the IRS, Madelyne's expertise is backed by memberships in the National Association of Enrolled Agents, the California Society of Enrolled Agents, the Sonoma County Executives Association, and the American Institute of Professional Bookkeepers. Madelyne has a background of 15 years in senior management positions in finance and technology, holds a B.S. degree from Georgetown University, and is pursuing a Master's in Taxation from Golden Gate University. When not working, Madelyne spends time with her wife and furry (canine) children, enjoys camping, working out, and watching the LPGA.

Christine Cromwell expert in bookkeeping, tax return preparation, and tax planning

Christine Cromwell Ingrassia, E.A.

Christine Cromwell, Enrolled Agent, established Cromwell Tax & Bookkeeping in 1983. Christine has expertise in bookkeeping, tax return preparation, and tax planning and is authorized to represent clients before the IRS. Christine is a member of the National Association of Enrolled Agents, the California Society of Enrolled Agents, the International Executives Association and the Sonoma County Executives Association. Christine has a B.A. degree in Business Management from Sonoma State University. When she is not working, Christine enjoys singing in the choir and spending time with her family, especially her grandchildren who are “just the cutest!”

Bonnie Grenfell is a bookkeeper at Cromwell Tax & Bookkeeping

Bonnie Grenfell, Bookkeeping

Bonnie has been a bookkeeper at Cromwell Tax & Bookkeeping since 2015. Prior to being a bookkeeper she was a claims adjustor for a national insurance company. She was born and raised in Petaluma and has a B.A. degree in Psychology from University of California, Berkeley. Bonnie lives in Petaluma with her high school sweetheart, the last of her three kids, and a very old cat. In her spare time she likes to walk with friends, read voraciously, and has started a raised garden bed in her backyard where she is growing organic vegetables and battling aphids. She travels to Oregon frequently to visit their daughter who lives outside Portland, and is just starting to travel internationally. Bonnie loves working at Cromwell Tax & Bookkeeping and taking care of her bookkeeping clients.

Christine Shappy is the Bookkeeper and the newest member of Cromwell Tax and Bookkeeping

Christine Shappy, Bookkeeper

Christine is the newest member of Cromwell Tax and Bookkeeping, bringing with her many years of bookkeeping experience through self-employment. She relates well with other small business owners and can appreciate their bookkeeping concerns. Christine lives in Sebastopol and enjoys the serenity of country living and the outdoors. She loves to travel and also enjoys hosting exchange students from around the world, considering each of them part of her international family. Christine has a compassion for animals, has two step-dogs, and recently adopted a feral kitten into her home. People and animals alike are always welcome at Christine’s house.

Ruth Dinauer is an administrative assistant at Cromwell Tax and Bookkeeping

Ruth Dinauer, Office Assistant

Ruth has spent her career as an administrative assistant for a diverse set of companies including her four years at Cromwell. When not working she enjoys spending time with her two Oregonian sons, going to the coast, knitting, and reading.

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