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OAHU Honolulu's Trusted Source for
BUSINESS TAX PREPARATION, FINANCIAL PLANNING, BUSINESS PLANNING, COMPREHENSIVE TAX PLANNING
● Tax Planning ●
●Business Tax Preparation and Filing ●
●Personal Tax Preparation & Filing ●
●Tax Advisory ●
●Financial Planning
Our Address
1441 Kapiolani Boulevard Suite 912
Honolulu, HI 96814
Oahu Business Tax Deadline & Compliance Center
Don't Let a Tax Deadline Become a Business Problem
Business owners have enough to manage without worrying about whether a federal or Hawaii tax return is due next week—or whether a deadline was already missed.
Diamond Head Tax Group helps businesses throughout Honolulu and Oahu with business tax preparation, tax filing, tax compliance and proactive tax planning.
Whether your company is an S Corporation, C Corporation, LLC or another business entity, our goal is to help you understand your obligations and stay ahead of important deadlines.
Know Your Business Tax Deadlines
Different business entities have different federal and Hawaii filing requirements.
S CORPORATIONS
Federal S Corporation income tax returns are generally filed using Form 1120-S and are generally due on the 15th day of the third month following the close of the tax year.
Hawaii S Corporations generally file Form N-35 and may have additional Hawaii tax requirements.
C CORPORATIONS
Federal C Corporations generally file Form 1120.
Calendar-year C Corporations generally have a federal filing deadline of April 15, while Hawaii corporate income tax returns are generally due April 20.
FISCAL-YEAR BUSINESSES
If your business operates on a fiscal tax year rather than a calendar year, your deadline may be different.
Don't assume another business's tax deadline is your deadline.
FILING AN EXTENSION?
An extension can provide additional time to complete and file an eligible tax return. However, business owners should remember an important rule:
An extension to file generally does not mean an extension to pay taxes that are due.
Proper planning before the original deadline can help determine whether estimated tax payments are necessary and how much cash should be reserved for taxes.
Missed Your Business Tax Deadline?
If you've already missed a deadline, don't panic—and don't ignore it.
Diamond Head Tax Group can help review your situation and determine the appropriate next steps.
We can help identify:
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Which federal returns may be required
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Which Hawaii returns may be required
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Whether an extension was filed
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Bookkeeping or recordkeeping issues affecting the return
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Whether estimated tax payments were made
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Whether additional tax may be due
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Potential late-filing or late-payment issues
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Tax-planning opportunities for the current and following tax year
The sooner a problem is addressed, the sooner you can get back on track.
Business Tax Preparation for Oahu Companies
Tax preparation is more than putting numbers into a tax return.
Your business tax return reflects the financial activity of your company throughout the year.
Diamond Head Tax Group provides business tax preparation and filing support for businesses in Honolulu and throughout Oahu. Our business tax services can include:
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Federal business tax return preparation
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Hawaii business tax return preparation
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S Corporation tax preparation
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C Corporation tax preparation
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LLC tax considerations
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General Excise Tax compliance
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Payroll tax considerations
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Estimated tax planning
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Business tax advisory
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Tax planning strategies
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Business financial planning
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Rental-property tax considerations
Rental Properties & Real Estate Tax Planning
Do you own rental property in Honolulu, Oahu or elsewhere in Hawaii?
Rental real estate can create significant tax-planning considerations.
Depending on your situation, we can help review areas such as rental income, deductible expenses, depreciation, property ownership structure and how rental activity interacts with your overall tax picture. The objective is to coordinate your business and rental-property tax strategy rather than treating each tax issue separately.
S CORPORATION TAX PLANNING
An S Corporation may provide tax advantages for some business owners, but the right strategy depends on the company's financial situation, ownership structure and individual circumstances.
Hawaii also permits eligible S Corporations to elect pass-through entity taxation subject to specific requirements.
That makes proactive planning particularly important. Before making a tax election or major business decision, we can help evaluate the potential federal and Hawaii tax consequences.
C CORPORATION TAX PLANNING
C Corporations have their own tax structure and planning considerations.Tax planning may involve reviewing:
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Business deductions
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Retirement planning
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Estimated taxes
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Compensation
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Cash flow
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Entity structure
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Business expansion
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Business succession
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Potential sale of the business
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Equipment and capital expenditures
Good tax planning starts before the tax return is prepared.
Great service. Professional help! When tax season comes around i'll be calling these guys! They provided me with a hassle free experience! Mahalo Diamond Head tax service!
Tax Preparation vs. Tax Planning
There is an important difference.
Tax preparation LOOKS BACKWARD
It analyzes what happened during the previous tax year and prepares the required returns.
Tax planning LOOKS FORWARD
It considers what you can do before the end of the current year to make informed financial and tax decisions.
At Diamond Head Tax Group, we believe the best results can come from combining both.
Why Oahu Business Owners Choose Diamond Head Tax Group
Diamond Head Tax Group is a Honolulu-based tax and financial services firm serving individuals and businesses in Hawaii.
Our services include business tax preparation and filing, tax planning, business planning, financial planning and related tax advisory services.
We take a personalized approach because every business has different goals, income levels, expenses, ownership structures and tax considerations.
Our focus is simple:
Help you stay compliant.
Help you plan ahead.
Help you make informed financial decisions.
Start Planning Before the Deadline
Waiting until the filing deadline can leave little time to identify problems or consider planning opportunities. Whether your business is preparing for its next tax filing, needs help with a late return or wants to develop a proactive tax strategy, Diamond Head Tax Group can help.
Serving Honolulu & Oahu Businesses
If you operate an S Corporation, C Corporation, LLC or another business in Hawaii, contact Diamond Head Tax Group for a business tax consultation.
Diamond Head Tax Group OAHU is Honolulu’s trusted personal and business tax firm, helping individuals, employees, and business owners prepare for the 2026 HAWAII TAX CHANGES through proactive tax planning across the OAHU ISLAND.
HONOLULU, OAHU, HAWAII
Diamond Head Tax Group OAHU - In Preparation with the 2026 Tax Changes in Hawaii With
Tax Planning Strategies from our Certified Tax Consultants
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DIAMOND HEAD TAX GROUP OAHU, staffed with experienced CERTIFIED TAX CONSULTANTS, provides expert guidance on the 2026 TAX CHANGES IN HAWAII.
We offer comprehensive TAX PLANNING SERVICES for INDIVIDUALS and BUSINESS OWNERS in HONOLULU, and also provide TAX ADVISORY SERVICES, TAX PREPARATION SERVICES, and many more, helping clients MAXIMIZE SAVINGS, stay COMPLIANT, and make INFORMED FINANCIAL DECISIONS.
HALEIWA, OAHU, HAWAII
Diamond Head Tax Group OAHU - In Preparation with the 2026 Tax Changes in Hawaii With Tax Planning Strategies from our Certified Tax Consultants
96712
96712 HALEIWA, OAHU, HAWAII is the gateway to Oahu’s North Shore, attracting both surfers and travelers seeking authentic Hawaiian culture. With its quaint boutiques, farmers’ markets, and iconic surf spots like Waimea Bay and Pipeline nearby, Haleiwa offers a vibrant mix of natural beauty, outdoor adventure, and local flavor.
DIAMOND HEAD TAX GROUP OAHU, led by expert CERTIFIED TAX CONSULTANTS, provides clear guidance on the 2026 TAX CHANGES IN HAWAII.
We specialize in TAX PLANNING SERVICES for INDIVIDUALS and BUSINESS OWNERS in HALEIWA and also offer TAX ADVISORY SERVICES, TAX PREPARATION SERVICES, and more, helping clients MAXIMIZE SAVINGS, stay COMPLIANT, and make STRATEGIC FINANCIAL DECISIONS.
KAPOLEI, OAHU, HAWAII
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Trust DIAMOND HEAD TAX GROUP OAHU, home to skilled CERTIFIED TAX CONSULTANTS, for insight on the 2026 TAX CHANGES IN HAWAII.
Our TAX PLANNING SERVICES for INDIVIDUALS and BUSINESS OWNERS in KAPOLEI are complemented by TAX ADVISORY SERVICES, TAX PREPARATION SERVICES, and more, designed to MAXIMIZE SAVINGS, ensure COMPLIANCE, and guide SMART FINANCIAL CHOICES.
KAILUA, OAHU, HAWAII
Diamond Head Tax Group OAHU - In Preparation with the 2026 Tax Changes in Hawaii With Tax Planning Strategies from our Certified Tax Consultants
96734
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DIAMOND HEAD TAX GROUP OAHU, featuring professional CERTIFIED TAX CONSULTANTS, helps clients navigate the 2026 TAX CHANGES IN HAWAII.
We provide tailored TAX PLANNING SERVICES for INDIVIDUALS and BUSINESS OWNERS in KAILUA, along with TAX ADVISORY SERVICES, TAX PREPARATION SERVICES, and more, empowering clients to MAXIMIZE SAVINGS, remain COMPLIANT, and achieve FINANCIAL SUCCESS.
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Our TAX PLANNING SERVICES for INDIVIDUALS and BUSINESS OWNERS in HAWAII KAI include TAX ADVISORY SERVICES, TAX PREPARATION SERVICES, and more, ensuring clients MAXIMIZE SAVINGS, stay COMPLIANT, and make INFORMED FINANCIAL DECISIONS.
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