Below is a chart of ratings for each Castle episode. The columns on 18-49 Ratings Share and Total Viewers (in millions) are final numbers, not initial numbers, except for those marked with an asterisk.
Season 1[edit]
All ratings figures for season 1 are initial numbers, not final.
Season 2[edit]
| Original Air Date
|
Episode Number
|
Title
|
18-49 Ratings Share
|
Total Viewers
|
| September 21, 2009
|
2.1
|
Deep in Death
|
2.3
|
9.43
|
| September 28, 2009
|
2.2
|
The Double Down
|
2.3
|
9.56
|
| October 5, 2009
|
2.3
|
Inventing The Girl
|
3.0
|
11.46
|
| October 12, 2009
|
2.4
|
Fool Me Once
|
2.4
|
9.99
|
| October 19, 2009
|
2.5
|
When The Bough Breaks
|
2.4
|
9.88
|
| October 26, 2009
|
2.6
|
Vampire Weekend
|
2.8
|
11.09
|
| November 2, 2009
|
2.7
|
Famous Last Words
|
2.4
|
9.68
|
| November 9, 2009
|
2.8
|
Kill The Messenger
|
2.5
|
10.72
|
| November 16, 2009
|
2.9
|
Love Me Dead
|
2.6
|
10.86
|
| November 23, 2009
|
2.10
|
One Man's Treasure
|
2.7
|
10.46
|
| December 7, 2009
|
2.11
|
The Fifth Bullet
|
2.3
|
8.41
|
| January 11, 2010
|
2.12
|
A Rose for Everafter
|
2.6
|
9.48
|
| January 18, 2010
|
2.13
|
Sucker Punch
|
2.8
|
9.44
|
| January 25, 2010
|
2.14
|
The Third Man
|
3.1
|
10.54
|
| February 8, 2010
|
2.15
|
Suicide Squeeze
|
2.5
|
9.48
|
| March 8, 2010
|
2.16
|
The Mistress Always Spanks Twice
|
2.4
|
9.01
|
| March 22, 2010
|
2.17
|
Tick, Tick, Tick. – (Part 1)
|
3.6
|
12.94
|
| March 29, 2010
|
2.18
|
Boom – (Part 2)
|
3.7
|
14.47
|
| April 5, 2010
|
2.19
|
Wrapped Up In Death
|
3.0
|
12.30
|
| April 12, 2010
|
2.20
|
The Late Shaft
|
3.2
|
13.1
|
| April 19, 2010
|
2.21
|
Den of Thieves
|
2.7
|
10.47
|
| May 3, 2010
|
2.22
|
Food to Die For
|
2.6
|
10.77
|
| May 10, 2010
|
2.23
|
Overkill
|
2.6
|
11.42
|
| May 17, 2010
|
2.24
|
A Deadly Game
|
2.4
|
10.1
|
Season 3[edit]
| Air Date
|
Episode Number
|
Title
|
18-49 Ratings Share
|
Total Viewers
|
| September 20, 2010
|
3.1
|
A Deadly Affair
|
2.7
|
10.7
|
| September 27, 2010
|
3.2
|
He’s Dead, She’s Dead
|
2.8
|
11.1
|
| October 4, 2010
|
3.3
|
Under the Gun
|
2.6
|
10.8
|
| October 11, 2010
|
3.4
|
Punked
|
2.7
|
10.7
|
| October 18, 2010
|
3.5
|
Anatomy of a Murder
|
2.5
|
10.9
|
| October 25, 2010
|
3.6
|
3XK
|
2.9
|
11.3
|
| November 1, 2010
|
3.7
|
Almost Famous
|
2.7
|
11.3
|
| November 8, 2010
|
3.8
|
Murder Most Fowl
|
2.5
|
10.8
|
| November 15, 2010
|
3.9
|
Close Encounters of the Murderous Kind
|
2.5
|
9.8
|
| December 6, 2010
|
3.10
|
Last Call
|
1.9
|
7.6
|
| January 3, 2010
|
3.11
|
Nikki Heat
|
2.4
|
9.6
|
| January 10, 2011
|
3.12
|
Poof, You're Dead
|
2.1
|
9.2
|
| January 24, 2011
|
3.13
|
Knockdown
|
2.4
|
9.1
|
| February 7, 2011
|
3.14
|
Lucky Stiff
|
2.5
|
9.3
|
| February 14, 2011
|
3.15
|
The Final Nail
|
2.2
|
8.8
|
| February 21, 2011
|
3.16
|
Setup
|
2.6
|
9.0
|
| February 28, 2011
|
3.17
|
Countdown
|
2.8
|
10.1
|
| March 21, 2011
|
3.18
|
One Life to Lose
|
3.1
|
12.0
|
| March 28, 2011
|
3.19
|
Law and Murder
|
3.2
|
12.6
|
| April 4, 2011
|
3.20
|
Slice of Death
|
2.8
|
10.5
|
| April 11, 2011
|
3.21
|
The Dead Pool
|
3.0
|
12.3
|
| May 2, 2011
|
3.22
|
To Love and Die in LA
|
2.9
|
12.1
|
| May 9, 2011
|
3.23
|
Pretty Dead
|
3.1
|
12.6
|
| May 16, 2011
|
3.24
|
Knockout
|
3.3
|
12.9
|
Season 4[edit]
| Air Date
|
Episode Number
|
Title
|
18-49 Ratings Share
|
Total Viewers
|
| September 19, 2011
|
4.1
|
Rise
|
3.2
|
13.3
|
| September 26, 2011
|
4.2
|
Heroes and Villains
|
3.1
|
11.6
|
| October 3, 2011
|
4.3
|
Head Case
|
2.5
|
11.2
|
| October 10, 2011
|
4.4
|
Kick the Ballistics
|
2.1
|
10.2
|
| October 17, 2011
|
4.5
|
Eye of the Beholder
|
2.5
|
11.2
|
| October 24, 2011
|
4.6
|
Demons
|
2.4
|
10.8
|
| October 31, 2011
|
4.7
|
Cops and Robbers
|
2.7
|
12.6
|
| November 7, 2011
|
4.8
|
Heartbreak Hotel
|
2.4
|
11.1
|
| November 21, 2011
|
4.9
|
Killshot
|
2.3
|
10.9
|
| December 5, 2011
|
4.10
|
Cuffed
|
2.0
|
8.1
|
| January 9, 2012
|
4.11
|
Til Death Do Us Part
|
2.3
|
9.8
|
| January 16, 2012
|
4.12
|
Dial M for Mayor
|
2.2
|
9.4
|
| January 23, 2012
|
4.13
|
An Embarrassment of Bitches
|
2.1
|
10.1
|
| February 6, 2012
|
4.14
|
The Blue Butterfly
|
2.0
|
8.7
|
| February 13, 2012
|
4.15
|
Pandora
|
2.0
|
8.9
|
| February 20, 2012
|
4.16
|
Linchpin
|
2.1
|
9.7
|
| February 27, 2012
|
4.17
|
Once Upon a Crime
|
2.1
|
9.1
|
| March 19, 2012
|
4.18
|
A Dance with Death
|
2.3
|
11.5
|
| March 26, 2012
|
4.19
|
47 Seconds
|
2.3
|
11.8
|
| April 2, 2012
|
4.20
|
The Limey
|
2.1
|
11.7
|
| April 16, 2012
|
4.21
|
Headhunters
|
2.1
|
11.2
|
| April 30, 2012
|
4.22
|
Undead Again
|
2.3
|
11.1
|
| May 7, 2012
|
4.23
|
Always
|
2.4
|
12.4
|
Season 5[edit]
| Air Date
|
Episode Number
|
Title
|
18-49 Ratings Share
|
Total Viewers
|
| September 24, 2012
|
5.1
|
After the Storm
|
2.1
|
10.45
|
| October 1, 2012
|
5.2
|
Cloudy with a Chance of Murder
|
1.9
|
10.35
|
| October 8, 2012
|
5.3
|
Secret's Safe With Me
|
2.2
|
10.61
|
| October 15, 2012
|
5.4
|
Murder, He Wrote
|
2.0
|
10.94
|
| October 29, 2012
|
5.5
|
Probable Cause
|
2.2
|
10.84
|
| November 5, 2012
|
5.6
|
The Final Frontier
|
1.9
|
10.02
|
| November 12, 2012
|
5.7
|
Swan Song
|
1.9
|
10.07
|
| November 19, 2012
|
5.8
|
After Hours
|
2.0
|
10.36
|
| December 3, 2012
|
5.9
|
Secret Santa
|
1.7
|
8.5
|
| January 7, 2013
|
5.10
|
Significant Others
|
1.9
|
8.66
|
| January 14, 2013
|
5.11
|
Under the Influence
|
1.9
|
9.14
|
| January 21, 2013
|
5.12
|
Death Gone Crazy
|
2.0
|
8.82
|
| February 4, 2013
|
5.13
|
Recoil
|
1.8
|
8.89
|
| February 11, 2013
|
5.14
|
Reality Star Struck
|
2.0
|
8.97
|
| February 18, 2013
|
5.15
|
Target
|
2.3
|
9.85
|
| February 25, 2013
|
5.16
|
Hunt
|
2.3
|
10.77
|
| March 18, 2013
|
5.17
|
Scared to Death
|
2.2
|
11.26
|
| March 25, 2013
|
5.18
|
The Wild Rover
|
2.1
|
10.57
|
| April 1, 2013
|
5.19
|
The Lives of Others
|
2.2
|
11.79
|
| April 15, 2013
|
5.20
|
The Fast and the Furriest
|
2.0
|
10.18
|
| April 22, 2013
|
5.21
|
The Squab and the Quail
|
2.3
|
11.76
|
| April 29, 2013
|
5.22
|
Still
|
2.0
|
10.53
|
| May 6, 2013
|
5.23
|
The Human Factor
|
2.0
|
10.84
|
| May 13, 2013
|
5.24
|
Watershed
|
2.1
|
11.16
|
Season 6[edit]
| Air Date
|
Episode Number
|
Title
|
18-49 Ratings Share
|
Total Viewers
|
| September 23, 2013
|
6.1
|
Valkyrie
|
2.2
|
11.46
|
| September 30, 2013
|
6.2
|
Dreamworld
|
2.2
|
10.88
|
| October 7, 2013
|
6.3
|
Need To Know
|
1.9
|
10.51
|
| October 14, 2013
|
6.4
|
Number One Fan
|
2.2
|
11.11
|
| October 21, 2013
|
6.5
|
Time Will Tell
|
2.1
|
10.7
|
| October 28, 2013
|
6.6
|
Get A Clue
|
2.1
|
10.69
|
| November 4, 2013
|
6.7
|
Like Father, Like Daughter
|
2.2
|
10.87
|
| November 11, 2013
|
6.8
|
A Murder is Forever
|
2.0
|
10.1
|
| November 18, 2013
|
6.9
|
Disciple
|
1.9
|
10.9
|
| November 25, 2013
|
6.10
|
The Good, the Bad, and the Baby
|
2.1
|
11.4
|
| January 6, 2014
|
6.11
|
Under Fire
|
1.7
|
8.9
|
| January 13, 2014
|
6.12
|
Deep Cover
|
1.9
|
9.03
|
| January 20, 2014
|
6.13
|
Limelight
|
2.0
|
8.96
|
| February 3, 2014
|
6.14
|
Dressed to Kill
|
2.1
|
10.02
|
| February 17, 2014
|
6.15
|
Smells Like Teen Spirit
|
1.7
|
7.75
|
| February 24, 2014
|
6.16
|
Room 147
|
1.7
|
8.69
|
| March 3, 2014
|
6.17
|
In the Belly of the Beast
|
1.6
|
8.38
|
| March 17, 2014
|
6.18
|
The Way of the Ninja
|
1.8
|
9.99
|
| March 24, 2014
|
6.19
|
The Greater Good
|
1.8
|
9.78
|
| April 21, 2014
|
6.20
|
That 70s Show
|
1.8
|
9.76
|
| April 28, 2014
|
6.21
|
Law and Boarder
|
2.0
|
10.39
|
| May 5, 2014
|
6.22
|
Veritas
|
1.6
|
9.00
|
| May 12, 2014
|
6.23
|
For Better or for Worse
|
2.1
|
10.59
|
Season 7[edit]
| Air Date
|
Episode Number
|
Title
|
18-49 Ratings Share
|
Total Viewers
|
| September 29, 2014
|
7.1
|
Driven
|
2.2
|
10.75
|
| October 6, 2014
|
7.2
|
Montreal
|
2.0
|
9.90
|
| October 13, 2014
|
7.3
|
Clear and Present Danger
|
1.9
|
9.17
|
| October 20, 2014
|
7.4
|
Child's Play
|
1.5
|
8.82
|
| October 27, 2014
|
7.5
|
Meme is Murder
|
1.6
|
8.75
|
| November 10, 2014
|
7.6
|
The Time of Our Lives
|
1.6
|
9.52
|
| November 17, 2014
|
7.7
|
Once Upon a Time in the West
|
1.8
|
9.38
|
| November 24, 2014
|
7.8
|
Kill Switch
|
1.7
|
9.55
|
| December 1, 2014
|
7.9
|
Last Action Hero
|
1.5
|
8.45
|
| December 8, 2014
|
7.10
|
Bad Santa
|
1.4
|
7.32
|
| January 12, 2015
|
7.11
|
Castle, P.I.
|
1.3
|
6.77
|
| January 19, 2015
|
7.12
|
Private Eye Caramba!
|
1.5
|
7.60
|
| February 2, 2015
|
7.13
|
I, Witness
|
1.4
|
7.41
|
| February 9, 2015
|
7.14
|
Resurrection
|
1.6
|
7.43
|
| February 16, 2015
|
7.15
|
Reckoning
|
1.6
|
8.47
|
| February 23, 2015
|
7.16
|
The Wrong Stuff
|
1.6
|
7.61
|
| March 16, 2015
|
7.17
|
Hong Kong Hustle
|
1.5
|
8.94
|
| March 23, 2015
|
7.18
|
At Close Range
|
1.4
|
8.04
|
| March 30, 2015
|
7.19
|
Habeas Corpse
|
1.5
|
8.16
|
| April 20, 2015
|
7.20
|
Sleeper
|
1.4
|
8.34
|
| April 27, 2015
|
7.21
|
In Plane Sight
|
1.3
|
8.31
|
| May 4, 2015
|
7.22
|
Dead From New York
|
1.4
|
8.26
|
| May 11, 2015
|
7.23
|
Hollander's Woods
|
1.4
|
8.44
|
Season 8[edit]
| Air Date
|
Episode Number
|
Title
|
18-49 Ratings Share
|
Total Viewers
|
| September 21, 2015
|
8.1
|
XY
|
1.2
|
6.84
|
| September 28, 2015
|
8.2
|
XX
|
1.2
|
6.70
|
| October 5, 2015
|
8.3
|
PhDead
|
1.2
|
6.76
|
| October 12, 2015
|
8.4
|
What Lies Beneath
|
1.1
|
6.78
|
| October 19, 2015
|
8.5
|
The Nose
|
1.1
|
6.67
|
| November 9, 2015
|
8.6
|
Cool Boys
|
1.0
|
6.07
|
| November 16, 2015
|
8.7
|
The Last Seduction
|
1.1
|
6.66
|
| November 23, 2015
|
8.8
|
Mr. & Mrs. Castle
|
1.1
|
6.65
|
| February 8, 2016
|
8.9
|
Tone Death
|
1.1
|
5.72
|
| February 14, 2016 (Sun)
|
8.10
|
Witness for the Prosecution
|
0.8
|
4.19
|
| February 15, 2016
|
8.11
|
Dead Red
|
0.9
|
5.15
|
| February 22, 2016
|
8.12
|
The Blame Game
|
1.1
|
5.48
|
| February 29, 2016
|
8.13
|
And Justice for All
|
1.1
|
5.26
|
| March 8, 2016
|
8.14
|
The G.D.S.
|
1.1
|
5.68
|
| March 21, 2016
|
8.15
|
Fidelis Ad Mortem
|
1.1
|
6.50
|
| April 4, 2016
|
8.16
|
Heartbreaker
|
1.1
|
6.37
|
| April 11, 2016
|
8.17
|
Death Wish
|
1.1
|
6.44
|
| April 18, 2016
|
8.18
|
Backstabber
|
1.0
|
5.86
|
| April 25, 2016
|
8.19
|
Dead Again
|
1.1
|
6.19
|
| May 2, 2016
|
8.20
|
Much Ado About Murder
|
1.0
|
6.03
|
| May 9, 2016
|
8.21
|
Hell to Pay
|
1.1
|
6.74
|
| May 16, 2016
|
8.22
|
Crossfire
|
1.3
|
7.65
|
