*540OPINION
Opinion by
Chief Justice MORRISS.In this dispute concerning drainage of a lake, two different judgments were signed, the first apparently signed July 12, 2002, favoring Ray and Carol Claxton, and the second signed July 19, 2006, favoring (Upper) Lake Fork Water Control and Improvement District No. 1. The Claxtons appeal from the 2006 judgment. Because we determine that the 2002 judgment became the final judgment in this case, we dismiss the appeal for lack of jurisdiction.
In order to explain our analysis, we provide a chronology of the lawsuit, including two substantial periods of inactivity. June 1996 Claxtons seek injunction against District.
11/4/1996 (Upper) Lake Fork, as third party plaintiffs, add Billy and Barbara Lynn as third party defendants.
3/26/1997 Claxtons add the Lynns as defendants.
6/19/1997 Claxtons seek summary judgment against all defendants.
6/18/2002 Claxtons file motion for partial summary judgment.
7/12/2002 Judgment signed. Court grants partial summary judgment, Clax-tons nonsuit all claims against Lynns, and all other claims against District, and District nonsuits all third party claims against the Lynns. Decretal language in judgment specifically renders judgment on all of the above and states that the judgment is final, that this is the final judgment, and that all relief not expressly granted is denied. The judgment is signed as “approved as to form and substance” by counsel for Claxtons and District.
9/6/2002 Judgment filemarked.
10/3/2002 District files motion for new trial.
11/15/2002 Order filed granting new trial.
8/22/2005 Claxtons again nonsuit Lynns.
9/1/2005 Claxtons file second motion for partial summary judgment against District, essentially same as original motion.
3/24/2006 District files motion for summary judgment.
3/27/2006 Claxtons file third motion for partial summary judgment against District, essentially the same as first and second motions.
7/19/2006 Final judgment signed.
1) Claxtons’ third motion for partial summary judgment denied.
2) District’s motion for summary judgment granted.
The question confronting us is jurisdiction. The failure of a jurisdictional requirement deprives a court of the power to act (other than to determine that it has no jurisdiction). Univ. of Tex. Sw. Med. Ctr. at Dallas v. Loutzenhiser, 140 S.W.3d 351, 359 (Tex.2004). And once a court determines that it has no jurisdiction, its only legitimate choice is to dismiss. State of Tex. v. Morales, 869 S.W.2d 941, 949 (Tex.1994).
The judgment containing a signature date of July 12, 2002, disposes of all claims and parties in this lawsuit, and not only states that it is the final judgment, but was approved both as to form and substance by counsel for the two remaining parties. It appears, from its face, that it was therefore final on that date. All of the relevant timetables begin to run on the date that a judgment is signed. A motion for new trial must be filed within thirty days of that date. Tex.R. Civ. P. 329b. The date on which a notice of appeal must be filed is also calculated based on the date on which the judgment is signed. Tex.R.App. P. 26.1.
*541If the July 12, 2002, judgment was the final judgment in this case, as it says it is, then we must determine whether the case was timely appealed with reference to that date. Using that date, only one result is possible — the notice of appeal filed September 18, 2006, was untimely and could not establish our jurisdiction.
We contacted the parties in connection with this issue, and have received briefing setting out their positions. Essentially, the Claxtons agree that the 2002 judgment is final, and now ask us to dismiss then-appeal for want of jurisdiction.
The District takes the position that we should disregard the notation on the judgment as to the date it was signed, because it was actually signed on the date it was ultimately filed. The extensive record provided contains nothing to support that position, other than the District’s pleadings. The trial court’s order granting the District’s motion for new trial states that the prior agreed judgment “entered on September 6, 2002 (but bearing the erroneous date of July 12, 2002) should be, and it is hereby in all things, vacated and set aside.”
Even if the trial court had the jurisdiction to grant the motion for new trial — which on its face it did not — and assuming that some error exists in the face of a judgment signed as correct in form and substance by all counsel, and even if this were a document properly rendering a new judgment, it does not state the correct date on which the judgment was signed, and could not be used by this Court to establish a signing date different from that on the face of the judgment.1
The question of our jurisdiction to hear an appeal of this case then depends on the determination of which of the two signed judgments is the valid one. There can only be one final judgment. Tex.R. Civ. P. 301. A trial court retains plenary power to grant a new trial or to vacate, modify, correct, or reform a judgment within thirty days after the judgment is signed. Tex.R. Civ. P. 329b(d); First Alief Bank v. White, 682 S.W.2d 251, 252 (Tex.1984). After the expiration of those thirty days, the trial court has no authority to set aside a judgment except by bill of review as provided by law. Tex.R. Civ. P. 329b(d); Thursby v. Stovall, 647 S.W.2d 953, 954 (Tex.1983).
The trial court lost its plenary power to vacate the judgment August 11, 2002. The trial court therefore had no jurisdiction to enter the November 15, 2002, order granting a new trial some 126 days after the signing of the first judgment. State ex. rel. Latty v. Owens, 907 S.W.2d 484, 486 (Tex.1995). Judicial action taken after the court’s jurisdiction over a cause has expired is a nullity. Id.
Even if both parties agreed that a different date actually existed, we are constrained by the rules to determine our jurisdiction by reference to the date on which the judgment was signed — a party cannot confer or waive jurisdiction by consent or agreement. Stine v. State, 908 S.W.2d 429 (Tex.Crim.App.1995). Appellate jurisdiction cannot be created by consent, stipulation of the parties, or waiver, either by the court or by litigants. Welder v. Fritz, 750 S.W.2d 930 (Tex.App.-Corpus Christi 1988, no writ). Jurisdiction is fundamental and cannot be ignored by this Court or waived by the parties. In re Marriage of Johnson, 595 S.W.2d 900, 902 (Tex.Civ.App.-Amarillo 1980, writ dism’d w.o.j.). Further, lack of appellate jurisdic*542tion is fundamental error, which can be raised by the court sua sponte. New York Underwriters Ins. Co. v. Sanchez, 799 S.W.2d 677, 679 (Tex.1990).
We have no option in this case but to recognize the state of the record before us and to act accordingly.
The appeal is dismissed for want of jurisdiction.
. An order nunc pro tunc, correcting only a true clerical error, may be granted by a trial court at any time, even after it has lost jurisdiction over the case. America's Favorite Chicken v. Galvan, 897 S.W.2d 874 (Tex.App.San Antonio 1995, writ denied).