Review your non-compete agreement (NCA) to first determine what state law governs it. Absent a "governing law" clause in the agreement, Washington State law likely applies, so long as your employer and/or you are based in Washington State.
No Bright Line Rule
Washington State law provides no bright line rule in determining whether a particular NCA is enforceable or not. Courts enforce an NCA only where principles of equity (fairness) are upheld. Essentially, the rule is that an NCA is enforceable so long as its restrictions are not greater than are reasonably necessary to protect the business or good will of the employer, even though they restrain the employee of his/her liberty to engage in a certain occupation or business, and deprive the public of the services, or restrain trade. Such determinations are made on a case-by-case basis, including the factors listed below:
Was a Contract Formed?
Did the employer offer marketable skills training to the employee in exchange for employee's promise to not compete? Such promise is usually in exchange for the employer training the employee on certain technology, skills, trade or knowledge.
Did the former employer's clients retain competitor's services prior to employee disengaging from former employer? Once disengaged, did the employee solicit former employer's current clients while working for competitor?
Time & Region
Is the duration and geographic reach of the restriction reasonable? A court will not enforce a restriction that unduly hinders the employee's efforts to earn a livelihood within a reasonable distance from the former employer.
Balance: harm to former employer v. hindering future livelihood of employee
The law promotes the reasonable exchange of services in the marketplace between employees and prospective customers, barring any substantial hardship imposed upon the former employer. Courts will consider whether employee's action has harmed former employer's business, as opposed to other competitor's providing such services to client, and whether the public's access is unnecessarily and unreasonably restricted to service and skill of the employee.