Accounting, Tax & Advisory · Long Island & New York metropolitan area

Accounting, tax, and advisory for privately held companies.

Build reliable financial operations, gain a clearer view of cash and performance, make tax decisions before the window closes, and be ready when a lender, external auditor, or buyer puts the numbers under greater scrutiny.

Best suited for: Established privately held businesses seeking an ongoing accounting and tax relationship—or focused support around a specific financial requirement.

John W. Halloran, Jr., CFA, and John W. Halloran, CPA
How can our family-led firm help your business?
Licensed New York CPA firm Established on Long Island in 2005 Business-focused accounting, tax & advisory
Where we can help

Start with what is happening in your business.

You do not need to choose an accounting service before reaching out. Most conversations begin with one of three business situations.

Your accounting function has not kept pace with growth.

You need a reliable close, useful reporting, and proactive tax planning without building every finance role internally.

Find out what to fix first: Accounting Operations Assessment

See How the Assessment Works

An external deadline is raising the standard for your financials.

A lender, investor, external auditor, buyer, or planned sale is creating new demands for accurate records and organized support.

Often includes: Client Accounting Services, Audit Readiness, or Transaction Advisory

Explore Financial Readiness

Management needs stronger controls and risk visibility.

You need a management-directed review of important processes or additional capacity for an existing internal-audit function.

Often includes: Internal Audit and focused advisory support

Explore Controls & Risk Support
What we do

Five capabilities. One coordinated relationship.

We combine ongoing accounting and tax support with focused help for external deadlines, transactions, and internal controls. From controller oversight through forward-looking financial advice, we help leadership see what changed, what is likely next, and what requires attention.

Why Halloran

Experienced judgment, applied directly to your business.

01

Established experience

The firm has served privately held businesses since 2005, with work scoped around each company’s needs and existing team.

02

Coordinated support

Accounting, business tax, readiness, and internal-control needs can be considered together as the company evolves.

03

Built around your existing team

We define responsibilities around the people, systems, and advisers already in place, adding only the capabilities the business needs.

Meet the firm

Established experience. Direct accountability.

Founded in 2005, John W. Halloran CPA, P.C. serves privately held businesses across Long Island.

Managing Partner John W. Halloran, CPA leads the firm’s professional accounting and tax practice. Managing Director John W. Halloran, Jr., CFA leads the firm’s CFO Advisory practice, as well as its business development, marketing, technology, and growth initiatives.

Established in 2005 Licensed New York CPA firm Based in Commack
Meet our leadership
Let’s talk

Tell us what your business needs next.

Tell us what is changing in your business and where you need support. We typically work with privately held companies seeking an ongoing accounting and tax relationship or focused readiness, controls, or transaction support. We generally respond within one business day.

Tell us about your business

Submitting this form does not create a client relationship. Please do not include Social Security or tax identification numbers, account information, tax returns, or confidential documents. We use the information you submit to evaluate and respond to your request and manage related communications.