An employer has no right to reject the resignation of its employee, for whatever reason. The law is that a notice of resignation of an appointment becomes effective and valid the moment it is received by the person or authority to whom it is addressed. This is because there is absolute power to resign and no discretion to refuse to accept; and it is not necessary for the person to whom the notice of resignation is addressed to reply that the resignation is accepted.
In the cases of Taduggoronno v. Gotom  4 NWLR (Pt. 757) 453 and Yesufu v. Gov. Edo State  13 NWLR (Pt. 731) 517, the courts held that it is not open to the employer for whatsoever reason to refuse to accept the resignation of the employee, for the employee has an absolute power to resign and the employer has no discretion to refuse to accept the resignation. See also the case of Adefemi v. Abegunde  15 NWLR (Pt. 895) 1.
It is not uncommon for Employee Handbooks to contain a clause that confers on the employer the right not to accept the resignation of an employee on grounds such as ‘on-going investigation’ and where the employee seeking to resign is under a contractual bond, the terms of which he is yet to finish serving. The courts have held such provisions to be unlawful and unenforceable. An employee has the right to resign with immediate effect, and to reject his rejection is tantamount to forced labour, and also against the time-honour labour law principle that an employer cannot force himself on an unwilling employee.
It is also common to find in the termination clause of some employment contracts that only the employer may make a payment in lieu of notice, while the employee is mandatorily required to give notice. The remedy available to the employer, where the employee, in such a case, resigns without notice would likely be damages and certainly not specific performance. In other words, such resignation would be treated as wrongful but not null and void.
In WAEC v. Oshionebo  12 NWLR (Pt. 994) 258, it was held that a notice of resignation is effective not from the date of the letter, or from the date of any purported acceptance, but from the date on which the letter was received by the employer or his agent; and that tendering of a letter of resignation by an employee carries with it the right to leave the service automatically without any benefit subject to the employee paying any of his indebtedness to his employer.
Thus, once an employee tenders his resignation, he ceases henceforth to be an employee, regardless of a rejection of the resignation by the employer. The employee’s resignation would have immediate effect even where he continues to come to work after his resignation is tendered.
Rejection of retirement
The distinction is however, made in cases of retirement. A letter of retirement does not necessarily take effect from the date that it is received by the employer. The case of WAEC v. Oshionebo  12 NWLR (Pt. 994) 258 made a distinction between “resignation” and “retirement” with different legal consequences. Resignation carries with it the right to leave service immediately and automatically without any benefit subject to the employee paying any of indebtedness to his employer. Retirement, on the other hand does not confer such a right to leave service immediately and automatically. A further legal consequence of retirement is provided for in OSHC v. Shittu  1 NWLR (Pt. 321) 476, the court held that where an employee gives notice of his voluntary retirement to his employer, and the employer refuses to accept the notice, the position is that the employee is still in the employer’s service. However, it is only the employee who can rely on that notice in his favour and not the employer who rejected the notice. This would be particularly relevant for the computation of terminal benefits. This is because it has to be adjudged not only a deviation from “natural equity” but also contrary to law for an employer who is guilty of the irregularity of refusing a notice of voluntary retirement to turn around and benefit from that irregularity.
See also Osu v. PAN Ltd  13 NWLR (Pt. 731) 627, where the court held that the notice of retirement will appropriately expire at the stipulated periods regardless of directives from the employer that the employee should stop work before the date stipulated; as such an employee remains a staff of the employer up to and including the last day when the notice would have properly expired.