What is the plan of Salvation?
According to Mormonism, the plan of salvation is God’s plan for his children. It is within the context of this plan that Mormons conceptualize the gospel of Jesus Christ. Thus, an understanding of the plan of salvation is necessary to understanding many of the tenants and doctrines of Mormonism.
There are three major parts to the plan of salvation: pre-mortality (pre-earth life), mortality, and post-morality.
Because the plan of salvation is so doctrinally expansive, we will include scriptural resources after each section for your own personal study.
In order to understand everything else in the plan of salvation, one must understand where we came from. Mormons believe that before we lived on the earth, we lived as spirit children of God. Indeed, Mormons believe that we are literal spirit children of God.  God, just like a father here on earth, wants his children to be happy. “For behold, this is my work and my glory—to bring to pass the immortality and eternal life of man” (Moses 1:39).
Mormons believe that it was during the pre-earth life that we learned of God’s plan to provide a savior, Jesus Christ, to atone for the sins of the world. Those who accepted God’s plan are born on the earth, but there were those who rejected God’s plan. Those who rejected God’s plan were cast out with Satan as his minions.
D&C 93:29; Hebrews 12:9; John 17:3
D&C 138:53–56; Abraham 3:22–26; Moses 3:5; Jeremiah 1:5
Mormons believe that Jesus Christ created the earth under the direction of God the Father. The earth was made for God’s children to come and have experience, and to tested and tried: “We will go down, for there is space there, and we will take of these materials, and we will make an earth whereon these may dwell; And we will prove them herewith, to see if they will do all things whatsoever the Lord their God shall command them” (Abraham 3:24-25). Thus the earth is central to God’s plan for his children.
1 Nephi 17:36; Moses 2:1; Alma 30:44; Moses 6:63; 2 Corinthians 5:6–7
Agency and the Fall of Adam And Eve
After the earth was created, God created Adam and Eve and placed them on the earth in the Garden of Eden. The earth existed in static state. There were two trees, the Tree of Life and the Tree of Knowledge of Good and Evil. God commanded Adam and Eve not to eat from the Tree of Knowledge of Good and Evil. God also gave Adam and Eve the agency they needed to choose for themselves. They chose to partake of the Fruit of the Tree of Knowledge of Good and Evil. The doctrine of the fall, according to Mormonism, is clearly taught in the Book of Mormon:
And now, behold, if Adam had not transgressed he would not have fallen, but he would have remained in the garden of Eden. And all things which were created must have remained in the same state in which they were after they were created; and they must have remained forever, and had no end.
And they would have had no children; wherefore they would have remained in a state of innocence, having no joy, for they knew no misery; doing no good, for they knew no sin.
But behold, all things have been done in the wisdom of him who knoweth all things.
Adam fell that men might be; and men are, that they might have joy. 
2 Nephi 2; Moses 3:15–17; Genesis 1:26–31; Genesis 2:15–17
2 Nephi 2:25; Moses 4; Genesis 3; Alma 12:22–34
Our Life on Earth
Mormons believe that our life here on earth is a time for us to prepare to become like God. According to Mormonism, God has a perfect, immortal, physical body. In order to become like God, his children must come to earth to obtain a body. Thus the earth life fulfills two major purposes: 1) it gives us the opportunity to test ourselves spiritually, and 2) it gives us the opportunity to obtain a body.
Another important facet of earth life is our living the gospel. God gives us the gospel through prophets, and expects us to obey his commandments are obtain the ordinances of the gospel.
Earth life also presents to barriers to becoming like God—sin and death. When we sin, we widen the separation between ourselves and God. When we die, our spirits are separated from our bodies. This is why Christ’s atonement is so important.
2 Nephi 2:21; Alma 12:21–24; Abraham 3:25–26;
2 Nephi 9:27; Alma 34:31–35; Mosiah 3:19; Alma 42:2–10;
2 Nephi 2:26–29; Joshua 24:15; Moroni 7:12–19; Romans 3:23; 1 John 1:8–10; 1 John 3:4
1 Nephi 10:20–21; 3 Nephi 27:19; Moses 6:57; Alma 41:10–11
Christ’s atonement overcomes both sin and death. The atonement of Jesus Christ is the reconciliation and redemption from sin. Through repentance we are able to obtain salvation through Christ’s atonement, and thus be enabled to overcome sin. The resurrection of Christ is another important part of Christ’s atonement, and it is the thing which will allow us to overcome death. Christ’s resurrection broke the bands of death, and all who have, or will ever, live on the earth will be resurrected. In this way, Christ’s atonement can be considered unconditional. Mormons testify that Jesus is the Christ. That he lives today as a resurrected being. That he did indeed atone for the sins of all the world. Mormons also testify that Christ’s atonement is the only way that we can return to live with God again.
And moreover, I say unto you, that there shall be no other name given nor any other way nor means whereby salvation can come unto the children of men, only in and through the name of Christ, the Lord Omnipotent. 
It is only through faith in Jesus Christ, repentance, and obedience to his commandments that we can truly overcome the effects of the fall and return to live in the presence of our Heavenly Father. It is only through the ordinances of the gospel that we can gain full access to the atonement of Jesus Christ.
2 Nephi 9:6–7; D&C 88:27–32;Alma 11:42–45; Luke 24:1–10, 36–39
Alma 40:23; 1 Corinthians 15:20–23; Helaman 14:15–19; 1 Corinthians 15:41–42
2 Nephi 2:6–8; D&C 19:15–19; 1 John 1:7;Alma 7:11–13; D&C 45:3–5
Alma 34:8–10; John 3:16–17; 2 Nephi 9:1–24; Alma 11:40; 3 Nephi 27
2 Nephi 31; 3 Nephi 11:31–41; Moroni 7:27–28
The Spirit World
Mormons believe that after we die our spirits will go to a place to await the resurrection. This place is called the spirit world. We take with us our experiences, and we are essentially the same person we were before we died. The gospel is preached to those who either never had an opportunity to hear the gospel, or who did not obey the gospel while they were on the earth. Ordinances are performed in temples for those who were unable to receive the gospel while they were on the earth. Mormons call this, the work for the dead.
Brethren, shall we not go on in so great a cause? Go forward and not backward. Courage, brethren; and on, on to the victory! Let your hearts rejoice, and be exceedingly glad. Let the earth break forth into singing. Let the dead speak forth anthems of eternal praise to the King Immanuel, who hath ordained, before the world was, that which would enable us to redeem them out of their prison; for the prisoners shall go free. 
Mormons believe that all mankind will hear and have the opportunity to choose to follow Christ at some point, whether in this life or the spirit world. In this way, God and Christ are truly no respecter of persons.
D&C 138; 1 Peter 3:19–20; 1 Peter 4:6; Alma 34:34; Alma 40:11–14; Ecclesiastes 12:7
The Resurrection, Judgment, and Immortality
When we are resurrected, we will be judged according to our works and our desires while on this earth. If we have repented, we will be covered by the atonement of Jesus Christ, and we will receive mercy. If we have not repented, we cannot receive the highest glories possible. We will all be resurrected, but we will not all be given eternal life, which is the life God wants for his children.
2 Nephi 9:14–15; Jacob 6:8–9; Alma 42:13–15, 22–23
2 Nephi 28:23; Alma 5:15–21; D&C 132:12; 137:9
Mosiah 3:23–25; Alma 12:12–14; John 5:22
Kingdoms of Glory
After we are resurrected, judged, and have obtained immortality, we will receive a reward from God. We will each be placed into a kingdom of glory. There are three kingdoms of glory:
1) The celestial kingdom is reserved for those who were valiant in their faith and testimony of Christ. Those who were truly converted and who have been faithful and endured to the end will live here. This is God’s abode. It is in the celestial kingdom that we can live with our families forever.
2) The terrestrial kingdom is reserved for those who were just men, but who were not faithful or valiant in their testimony of Christ. Those who live in this kingdom will be happy, but they will not be able to live with their families forever. There are no family relationships in this kingdom.
3) Finally, the telestial kingdom is reserved for those who lived sinful and unrepentant lives. There are no family relations here. These people will pay for their own sins, and then they will live with a level of happiness.
Each kingdom of glory will be a place a joy and happiness, but only the celestial kingdom will be a place for the fullness of joy, which is obtained through marriage and family relationships.
3 Nephi 28:10; D&C 137; 1 Corinthians 15:41–42
D&C 76: Introduction; Matthew 5:48; 1 Corinthians 15:40
2 Nephi 31:17–21; D&C 45:8; John 3:16
D&C 14:7; D&C 93:19; John 17:3; D&C 29:43–44
 See Hebrew 12:9 and Romans 8:16.
 2nd Nephi 2:22-25.
 Mosiah 3:17.
 D&C 128:22.