Here’s a tip: [ul] [li] “Adviser” is older and more common in British English. [/li] [li] “Advisor” is most commonly used in North American English and is generally considered more formal than “adviser.”[/li] [li]For professional titles, use the spelling preferred by the industry or employer. [/li] [/ul]

Advising is a weighty responsibility. Bad advice can have unfavorable consequences. Take the case—no pun intended—of Jacob Stadfeld. When a district attorney’s office subpoenaed him during an investigation of a disappearance, he consulted a lawyer. The lawyer advised him to avoid the proceedings and to offer to meet with the district attorney informally in exchange for immunity. Jacob listened. He met with the county’s DA, who must have been quite affable because Jacob opened up about his dubious past. Shortly thereafter, he was indicted for marijuana trafficking, based on the incriminating evidence he revealed during the informal get-together. Before discussing whether the lawyer’s advice was subpar, let’s talk about what Jacob wanted his lawyer to be—an advisor or an adviser. What’s the difference?

For one thing, adviser is the older of the two terms. It’s an example of a noun derived from a verb (a nominalization). In this case, the verb was advise. Advise, when used with a direct object, means to give counsel, to recommend, or to give information. Without an object, it means to take counsel. In 1915, the noun adviser was first recorded as referring to a military person sent to a foreign country to render aid.

If you look in the dictionary now, you will find multiple definitions for adviser. Logically, an adviser is someone who gives advice. In education, it refers to a teacher who advises students on academic issues. In the British educational system, it refers to a subject specialist who advises schoolmasters on teaching methods and facilities. It’s also another name for a fortuneteller. The -er spelling is most common in the United Kingdom, Ireland, and Asia. Two notable examples from the United Kingdom are the Professional Adviser Awards, presented in the United Kingdom by a panel of financial advisers, and Adviser magazine, published by the Citizens Advice service.

Advisor is most likely to appear in American English writing. When adviser appears, it may be considered less formal than advisor. Perhaps this is because advisor is the most commonly used form in official job titles of both the United States and Canada. In an online comment, one native English speaker identified as “Germ” remarked that he had never personally encountered “adviser” and that “it just looks wrong.” He worried that if he used “adviser” on his business cards, potential clients would think he didn’t know how to spell. “It would do me little good to point out that a dictionary says they’re both correct.” For him, adviser is a business risk he wasn’t willing to take.

Where did the -or ending originate? comments that it might be a back-formation from advisory. Although advisor is common, you will see adviser in American English, especially in quoted material from other countries. Some media outlets commonly adopt the -er ending for their publications and events. An example is the Women Adviser Summit, hosted by Investment News magazine.

Do professionals, the ones who bear these titles, have an opinion? Yes, according to a 2014 article by Christopher Carosa. He claims that brokers usually refer to themselves as advisors. “Not all aspects of financial planning and financial advice require providing investment advice. . . Why invite potential compliance headaches by calling these people ‘advisers’?” There are professionals in the industry who do give counsel, and they are called registered investment advisers. The New York Times published Susan E. Rice’s official job title as National Security Adviser. If you quote or refer to someone’s position, most experts agree that you shouldn’t change the spelling of a formal job title according to your own preference. In fact, the Chicago Manual of Style forbids it.

Based on his attorney’s advice, Jacob Stadfelt thought that his “immunity” applied to any crimes that he disclosed in the casual conversation with the district attorney. He was wrong. So was Jacob Stadfeld’s lawyer an advisor or an adviser? Appellate Judge Diane Sykes didn’t quibble about spelling when she reviewed the case. The previously quoted article reports her ruling: “Bad advice from lawyers is no excuse for poor judgment in deciding who to spill your guts to.” It’s clear, then: being an advisor or an adviser is not a responsibility to take lightly. Depending on your audience, you might vary on which spelling you favor. If you can’t decide, you can always opt to use a synonym such as counselor… or is it counsellor?

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