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Best Business Lawyers Ontario, CA

Our Recommended Best Ontario Business Lawyers

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Our goal is to connect people with the best local professionals. We scored Ontario business lawyers on more than 25 variables across five categories, and analyzed the results to give you a hand-picked list of the best.

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13Top Picks

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Providers

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Best Business Lawyers Serving Ontario
Ontario, CA
Visit WebsiteLicense: Verified

Expertise.com Rating

Review Sources

Avvo
5.0 (5)

Why choose this provider?

Renowned tax and business attorney Johnny Luna specializes in bitcoin taxation. Serving Henderson and the rest of California, he assists clients in comprehending the intricacies and tax implications of cryptocurrency transactions. He effectively helps people who have made cryptocurrency investments submit reports to the IRS. Luna's unique background as an international tax legal editor for Bloomberg Tax and an IRS tax office legal fellow for the National Taxpayer Advocate has allowed him to successfully execute over 100 bitcoin reconciliations. By sharing his expertise on various social media platforms, he is also dedicated to giving back to society.

  • Business Formation
  • Cryptocurrency and Taxation Research
  • Cryptocurrency Taxation reporting
  • Cryptocurrency IRS Audit

Best Business Lawyers Serving Ontario
Ontario, CA
Visit WebsiteLicense: 5537089

Expertise.com Rating

Why choose this provider?

Legal challenges can disrupt even the most successful businesses, but with the right legal guidance from Charles Slamowitz, companies can turn obstacles into opportunities. A highly regarded business attorney serving clients in Ontario and across California, Charles specializes in emerging tech, and he is adept at high-stakes litigation and regulatory compliance. He has successfully advised over 150 clients, including high-profile brands like Alfa Romeo Formula One, the New York Mets, and U.S. Olympics, on legal strategies that protect their interests and foster growth. Slamowitz has also been a NYT.NYC speaker on topics covering business law and digital regulations, and he continues to shape the industry with his forward-thinking legal insights.

  • Business Contracts
  • Business Transactions
  • Al Risk Mitigation
  • Blockchain Compliance
  • Shareholder Agreements
  • Business Litigation
  • Compliance & Risk Management
  • Blockchain
  • A.I.
  • Crypto

Best Business Lawyers Serving Ontario
1131 W. 6th Street, Suite 227 ​, Ontario, CA 91762

Expertise.com Rating

Review Sources

Avvo
4.0 (3)
Google
5.0 (1)

Why choose this provider?

The Law Office of Gurjit Singh provides legal services to businesses at all stages of their operations, from business formation to drafting, negotiating, and reviewing contracts. The law firm serves Ontario businesses of all types and sizes, advising clients on various types of business transactions, determining a business's assets, liabilities, and interests, and the purchase, sale, or dissolution of a business. Gurjit Singh also practices in the area of real estate law and offers his legal services in English, Punjabi, and Urdu.

  • Business Formation

Best Business Lawyers Serving Ontario
24910 Las Brisas Road Ste #102, Murrieta, CA 92562

Expertise.com Rating

Review Sources

Avvo
5.0 (3)
Google
5.0 (2)
Yelp
1.0 (1)

Why choose this provider?

Messina & Hankin LLP offers counseling and court representation to business entities in Ontario and the neighboring communities. It litigates cases involving contract breaches, commercial disputes, unfair trade practices, and lender liability claims. It also deals with matters related to mergers and acquisitions, contract drafting and review, and business formation. Other practice areas include estate planning and employment law. The company's founding partner, John A. Messina Jr., has published three articles in The Valley Business Journal since 2017.

  • Business Formation

Best Business Lawyers Serving Ontario
10788 Civic Center Dr, Rancho Cucamonga, CA 91730

Expertise.com Rating

Review Sources

Avvo
5.0 (17)
Google
4.8 (16)
Facebook
5.0 (3)

Why choose this provider?

The Law Office of Scott J. Sheldon serves the communities in and around Ontario. The firm handles various aspects of business law and offers resolution to disputes, whether they are external or internal. Some of the matters it handles include breaches of contract and warranty, civil fraud and misrepresentation, unfair business practices, breaches of fiduciary duty, shareholder disputes, and product liability. Scott Sheldon had been in the legal field for two years before he founded his firm in 2014.

  • Business Contract Review
  • Business Litigation

Best Business Lawyers Serving Ontario
3200 E. Guasti Road Suite 100, Ontario, CA 91761

Expertise.com Rating

Review Sources

Avvo
4.5 (25)
Google
4.0 (4)

Why choose this provider?

Usher Law Group provides counsel and representation to individuals, families, and business owners in Ontario and the surrounding areas. Its team assists clients in business law-related matters, such as entity formation, trademark protection, employee stock ownership plan, property agreement, and business acquisition and dissolution to help them maximize their profits, minimize losses, and create tax savings. A member of Wealth Counsel, founder Charlene L. Usher also takes on estate planning, probate, and conservatorship matters. She has been in practice since 1997.

  • Business Formation

Best Business Lawyers Serving Ontario
5857 Pine Avenue, Suite B, Chino Hills, CA 91709

Expertise.com Rating

Review Sources

Avvo
5.0 (8)
Facebook
5.0 (7)

Why choose this provider?

Otten Law, PC Attorneys, is a multi-practice firm serving people and companies in Ontario. It offers legal guidance to clients dealing with business-related matters, and the team helps them address breach of contract, trademark and intellectual property, and business formation issues. The practice also takes on cases involving business funding, competitive negligence, and contract negotiation and creation. Its founder, Victor Otten, has been practicing law for over 15 years. He also deals with criminal, real estate, and environmental law cases.

  • Business Formation
  • Business Litigation
  • Mergers & Acquisitions

Best Business Lawyers Serving Ontario
13831 Roswell Ave., Ste. D, Chino, CA 91710

Expertise.com Rating

Review Sources

Facebook
5.0 (8)
Avvo
5.0 (2)

Why choose this provider?

Voorhees Law Group PC serves people and companies in Ontario. It provides personalized representation in different aspects of business law. The firm offers business management, formation, planning, and restructuring services to protect clients' financial and emotional health. It creates business plans to preserve profits and mitigate legal risks. It also deals with cases related to asset protection, trust administration, and estate planning. Kariann Voorhees, the managing partner, is a board member of the Exit Planning Institute—Orange County Chapter.

  • Business Formation

Best Business Lawyers Serving Ontario
1317 W. Foothill Blvd, Suite 245, Upland, CA 91786

Expertise.com Rating

Review Sources

Google
5.0 (30)
Facebook
3.6 (8)
Yelp
5.0 (4)

Why choose this provider?

Golden Oaks Law Group, LLP, caters to clients in Ontario. It advises startups regarding business entities, which includes working with their accountants to enumerate the pros and cons of each type. Once they have made an informed decision, the firm assists in forming the business and maintaining corporate records. It also creates succession plans, helping entrepreneurs transfer business interests in the event of retirement and death. Suzanne M. Graves, the practice's founder, is an advisory board member of the National Network of Estate Planning Attorneys.

  • Business Formation

Best Business Lawyers Serving Ontario
9431 Haven Avenue, Suite 114, Rancho Cucamonga, CA 91730

Expertise.com Rating

Review Sources

Avvo
5.0 (4)

Why choose this provider?

The Law Offices of Tiffany D. Cardoza, Attorney & Counselor at Law, serves Ontario businesses and people. For over 20 years, it has been working with small and family-owned businesses. The firm offers consultation services to help entrepreneurs determine the right form of organization for their enterprise. It also addresses issues involving taxation, wealth management, and business entity formation. Tiffany Cardoza, the founding partner, is a member of the National Association of Tax Professionals and the National Notary Association.

  • Business Formation

Best Business Lawyers Serving Ontario
1365 West Foothill Boulevard Suite 2, Upland, CA 91786

Expertise.com Rating

Review Sources

Avvo
4.5 (8)

Why choose this provider?

Torrence L. Howell, Attorney at Law, caters to small and large businesses in Ontario. With over 20 years of legal experience and a background in business, including a degree in accounting and an MBA, the attorney offers insightful advice on business litigation matters such as breach of contract and partnership dissolution. He also represents clients in LLC formation and corporate restructuring. Torrence Howell has served as treasurer for the Western San Bernardino County Bar Association.

  • Business Contract Review
  • Business Formation

Best Business Lawyers Serving Ontario
8577 Haven Avenue Suite 110, Rancho Cucamonga, CA 91773

Expertise.com Rating

Review Sources

Avvo
5.0 (1)

Why choose this provider?

OsbornLaw caters to small enterprises and Fortune 500 companies in Ontario seeking legal help in business litigation matters. It represents them in cases concerning unfair trade practices and competition, intellectual property, unlawful employment practices, and construction defects. Founder Richard G. Osborn leverages his experience as a former chair for a national law firm in protecting their interests before the U.S. Supreme Court and the U.S. Court of Appeals. In 2009, he received the Man of the Year in Law award from the American Biographical Institute.

  • Business Litigation
  • Business Formation

Best Business Lawyers Serving Ontario
3200 Guasti Rd. Ste 100, Ontario, CA 91761

Expertise.com Rating

Review Sources

Facebook
5.0 (5)
Yelp
5.0 (1)
Avvo
5.0 (1)

Why choose this provider?

Empire Business Law is a non-litigation firm serving areas in and around Ontario. Since 2020, it has been assisting clients in launching their startup companies, raising their capital safely, and protecting their intellectual properties. The practice drafts and reviews employment manuals, handbooks, and agreements. Its team also takes on cases related to mergers and acquisitions and trademark applications. Daniel Lopez, the founding partner, translates complex legal concepts into practical advice to help business owners achieve their goals.

  • Mergers & Acquisitions
  • Business Formation

Compare Best Ontario Business Lawyers

NameExpertise RatingAddressPromotionsLearn more
Mr. Crypto Tax Law PLLC
Ontario, CACall for consultation
Slam Legal
Ontario, CACall for consultation
Law Office of Gurjit Singh
1131 W. 6th Street, Suite 227 ​, Ontario, CA 91762
Messina & Hankin LLP
24910 Las Brisas Road Ste #102, Murrieta, CA 92562
Law Office of Scott J. Sheldon
10788 Civic Center Dr, Rancho Cucamonga, CA 91730
Usher Law Group
3200 E. Guasti Road Suite 100, Ontario, CA 91761
Otten Law, PC Attorneys
5857 Pine Avenue, Suite B, Chino Hills, CA 91709
Voorhees Law Group PC
13831 Roswell Ave., Ste. D, Chino, CA 91710
Golden Oaks Law Group, LLP
1317 W. Foothill Blvd, Suite 245, Upland, CA 91786
The Law Offices of Tiffany D. Cardoza Attorney & Counselor at Law
9431 Haven Avenue, Suite 114, Rancho Cucamonga, CA 91730
Torrence L. Howell Attorney at Law
1365 West Foothill Boulevard Suite 2, Upland, CA 91786
OsbornLaw
8577 Haven Avenue Suite 110, Rancho Cucamonga, CA 91773
Empire Business Law
3200 Guasti Rd. Ste 100, Ontario, CA 91761

Disclaimer:  Consumers utilizing Expertise.com are free to communicate and contract with any lawyer they choose. Expertise.com is not involved in the confidential attorney-client relationship. Featured lawyers pay a reasonable advertising cost to market their legal services with Expertise.com and must meet similar selection criteria as other lawyers. All cases are different. Prior results do not guarantee a similar outcome.