Audit & Assurance Services for Businesses.

Audit & Assurance Services for Businesses in Chicago, IL

At Lewis CPA, we’ve been providing auditing and assurance services to clients nationwide for almost forty years. Based in Chicagoland, we are a team of accounting professionals dedicated to easing the burden of a financial statement audit so you can present your business results with confidence.

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Audit & Assurance Services for Businesses.
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4000+ Happy Clients
We service 1,000+ businesses and 3,000+ individual clients, many of them located nationwide.
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38 Years of Experience
Since 1986, we’ve provided comprehensive tax and accounting solutions for individuals and businesses.
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Serving 52 States
With our technology stack, we provide remote accounting services for you and your business, regardless the location.

Professional Financial Statement Audit

We are committed to providing a full range of exceptional accounting services. We audit firms in Chicago and across the country, offering tax preparation, IRS representation, financial statements, limited assurance, and reasonable assurance. Our professional staff works with small family operations and large corporations, providing stability and security to allow businesses to confidently go about doing what they do best.

Minimize Your Taxes

Our Audit & Attest Services

Business is built on the numbers – we’ll help you understand them. Accurate financial reporting gives you the certainty you need to manage your business and grow into the future.

Financial Statement Audit

Lewis has ranked among Chicago’s elite financial auditing companies for decades. We provide expert financial statement audits to small businesses, non-profits, and corporations of all sizes.

Financial Statement Review

Not everyone needs a full-scale audit. Sometimes a financial statement review can provide all the information required at a much lower cost and we offer these services as well.

Financial Statement Compilation

Financial statement compilations offer less assurance than a review. Often, all you will need is help to prepare statements for presentation, and we can provide you with excellent service at attractive rates.

Agreed-Upon Procedures

Perhaps you have very specific needs outside the scope of a full financial statement. We can help with agreed-upon audit services in whatever area you require, from simple contracts to regulation compliance to testing accounting software.

Internal Audits

At, we provide companies with peace of mind through internal audit services. Understanding the full scope of your business’ finances, internal controls, and risks can help you maximize efficiency – and profits.

Keep your books in order

Our expert staff has centuries’ worth of professional experience in auditing and assurance. Confidence is just a phone call or email away.

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Audit Services for Your Business

At Lewis CPA, we provide financial audit services for small businesses – and large companies. Whether you’re a corner grocery, a huge law firm, a mid-sized contractor, or a not-for-profit agency, we can give you a clear understanding of your organization’s financials.

We work with a wide range of retailers in Chicagoland and beyond. We can help you understand your numbers, from financial statements to tax preparation to inventory management.

Law firms are a particular Lewis CPA specialty – we’re here to represent you. We can give you an accurate understanding of your business's financial footing, through audits, financial forecasting, statements, and more. We’ll also ready you for tax time and provide expert counsel in any IRS audit.

How do you build a strong construction company? By having a stable financial foundation. We can give you that through consultation, financial statements, and reasonable assurance.

We offer a full range of not-for-profit audit services to community service organizations, hospitals, environmental organizations, schools – and everyone else who’s not in it for the money. These include financial statements, reviews, internal audits, and more.

Why Choose Our Audit Firm

Why Lewis CPA? We are a professional, certified accounting firm with deep expertise and a sterling reputation known far and wide. Simply put we’re reliable, dependable, and stand behind our work.

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Remote services

With today’s technology, we can help anyone anywhere by leveraging video conferencing and cloud technology.
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Whether onsite or across the web, we work in every corner of the country.
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Deep expertise

Our staff has been delivering for companies large and small for more than four decades, bringing a wealth of experience to your books.
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At Lewis CPA, we are problem solvers. When it comes to accounting and auditing services, we’ll face any issue and handle it – so you don’t have to.

Our Business Audit Process

Our team has business auditing down to a science. And our step-by-step process will keep you up-to-date and informed all along the way.

Our Expat Tax Planning Process.
  • Planning

    Our staff will meet with your management, study your organization, come up with goals and objectives, and draw up a framework. Then we’ll provide you with a memo of the scope of the project so that you understand all aspects.

  • Fieldwork

    Fieldwork puts into practice the accounting and auditing you requested. We’ll thoroughly review your books, talk to key players, conduct surveys, and analyze all financial aspects of your business. This can be done remotely or onsite.

  • Review

    Once fieldwork concludes we’ll review our findings, giving you details and insights into your company’s finances. We’ll draft an initial report – and then go over it thoroughly with management. Again, locally or via video conferencing.

  • Reporting

    The final report represents the last step of the process. This is the fully-fledged audit or financial statement that was agreed upon. When we’re done, you’ll have a deep understanding of your company’s financial standing.

Business Audit & Assurance FAQs

  • How much do auditing services cost?

    Audits and financial statements vary widely in price, depending upon their size and scope. A small company may take less time and cost relatively less, whereas a large corporation can take months and be far more expensive. We’ll be straight with you right from the beginning.

  • Can a non-CPA prepare financial statements?

    Want to do your own books? The law allows non-CPAs to compile financial statements but not to officially prepare them. And would you really want to? Your numbers are critical to the success of your business. Why risk putting them in the hands of an amateur? With our team, your finances are in the best hands possible.

Client Reviews

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Susan & her entire staff are absolutely wonderful!  They are so kind both on the phone and in person.  Susan makes a point to have a wide range of appointment times to accommodate everyone.
Grace Soraparu
I learned about Susan from some co-workers and after hearing all their positive remarks, I made an appointment with her. BEST financial/tax decision I have ever made!
Kevin Thornton
Many thanks as always. Truly unbelievable how fast you respond. 5 star service.
Kathy G
Very professional, prompt ad well informed. Outstanding!
Gary Fansler
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Reach Out to Your CPA

At Lewis, your books are our priority. Let us help you understand your company from the inside out. Whether you are a local Chicagoland business or a major nationwide corporation, we’re here to help you with all your accounting and auditing needs.

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