MARTIN, Judge.

In her first assignment of error, appellant contends that her motion, dated 19 March 1976, to vacate and set aside the 10 March 1975 judgment should have been granted since there was a failure to comply with the North Carolina Rules of Civil Procedure. More specifically, she argues that she was never properly made a party to this action since G.S. 1A-1, Rule 25(a) states that a personal representative may be substituted for a deceased party only by a supplemental complaint if more than one year has passed since the deceased party’s death. We agree with this argument.

Upon reviewing the facts in the instant case, we have concluded that the appellant and the appellee were both improperly substituted as parties in this action. Under G.S. 1A-1, Rule 25 (a) there is a provision for substitution upon the death of a party. This rule provides as follows:

“(a) Death. — No action abates by reason of the death of a party if the cause of action survives. In such case, the *691 court, on motion at any time within one year thereafter, or afterwards on a supplemental complaint, may order the substitution of said party’s personal representative or successor in interest and allow the action to be continued by or against the substituted party.” G.S. 1A-1, Rule 25 (a).

Rule 25(a) therefore limits the time within which a motion for substitution may be made to one year following the death of a party. The rule, however, is not a hard and fast limitation on substitution since the court may also order substitution after a supplemental complaint has been filed. Thus if a motion for substitution is made and granted within the one year period, it is not required that a supplemental complaint be filed unless there is a desire to allege other new matters. However, if the one-year period has run, the court has no authority to order substitution without the filing of a supplemental complaint.

In the case at bar, the original plaintiff, Jerry E. Beding-field, died on 21 July 1968 and the original defendant, Forrest Fisher, died on 11 March 1969. Both of the original parties died after the complaint and answer were filed but before the case ever came to trial. After their deaths, no further efforts were made to prosecute the action and no further papers were filed until four years later. On 8 May 1973, Don Garren, attorney for original plaintiff, attempted to substitute Larry Bedingfield and Pamela Bedingfield, the original plaintiff’s heirs, as plaintiffs in this action and to substitute Elsie Fisher, the original defendant’s wife, as defendant. Since both of the original parties had been deceased for more than one year, the only proper mode of substitution at that time was by supplemental pleadings under Rule 25(a). We note, however, that the attempted substitution of the parties was by a motion to amend the original complaint, presumably filed pursuant to G.S. 1A-1, Rule 15, rather than by a supplemental -complaint as required by G.S. 1A-1, Rule 25(a). Nevertheless, the trial court allowed such a method of substitution on May 8, 1973.

Without discussing the matter at length, it suffices to say that the differences between an amendment and a supplemental complaint have already been decided by this Court. Williams v. Freight Lines and Willard v. Freight Lines, 10 N.C. App. 384, 179 S.E. 2d 319 (1971). See also G.S. 1A-1, Rule 15(a) and (d). It is therefore apparent that, prior to the appellant’s mo *692 tion to vacate and set aside the judgment in this case, neither of the parties had been properly substituted by supplemental complaint in accordance with G.S. 1A-1, Rule 25(a). Thus, the trial judge erred in refusing to grant the appellant's motion. Moreover, since Larry and Pamela Bedingfield, and later Robert Deutsch, were never properly substituted as plaintiffs, it is not necessary for us to discuss their contention that the appellant waived, by appearing, her right to argue on appeal that she was improperly substituted as a defendant to this action.

Even if we assume, arguendo, that the attempt to substitute the parties was not by amendment but rather was by supplemental pleading, as required by G.S. 1A-1, Rule 25(a), we would nevertheless be compelled to reach the same result for yet another reason. In order for a supplemental pleading to be procedurally proper, it must satisfy the requirements of G.S. 1A-1, Rule 15(d). Under this rule, it is stated:

“(d) Supplmental pleadings. — Upon motion of a party the court may, wpon reasonable notice and wpon such terms as are just, permit him to serve a supplemental pleading setting forth transactions or occurrences or events which may have happened since the date of the pleading sought to be supplemented, whether or not the original pleading is defective in its statement of a claim for relief or defense. . . .” G.S. 1A-1, Rule 15(d) (emphasis added).

The language of this rule “. . . the court may . . . upon such terms as are just . . .” permits but does not require a trial court to allow a supplemental pleading. In any event, it does not appear to be a matter of right, and it seems clear that a court may deny a supplemental pleading to substitute parties if the allowance of such a pleading would be unjust.

In the case at bar, we note that substitution was attempted on May 8, 1973, more than four years after the death of the original parties. However, the record fails to reveal any findings by the trial judge as to whether this or any other factor was ever considered in determining if the supplemental pleading was “just.”

It must also be emphasized that G.S. 1A-1, Rule 15(d) requires a supplemental pleading to be “upon reasonable notice.” We have carefully examined the record and cannot find any in *693 dication that Elsie Fisher was ever served with notice of the attempt to substitute the parties in this action. To the contrary, a motion to substitute the parties by amending the original complaint was filed by Don H. Garren on the 8th day of May 1973 and no notice of this motion was ever served upon Elsie Fisher. Because of this lack of notice, the supplemental pleadings allowed by the court on 8 May 1973 were never in compliance with the requirements set forth in Rule 15(d) and, hence, were improperly allowed by the trial court. Since the supplemental pleadings were improper, it follows that the attempted substitution of parties by the supplemental pleadings was also improper and, therefore, that both parties were improperly joined to this action. Once again, since Larry and Pamela Bedingfield, and later Robert Deutsch, were never properly substituted as plaintiffs in this action, it is not necessary for us to discuss their argument that appellant waived, by appearing, her right to contest improper substitution of parties.

Reversed and remanded.

Judges Parker and Arnold concur.