TFPL, March 2003: I have seen his entry in the record books of the College of Arms.
He had been granted a beautifully painted new crest of a dragon's arm. and all of his family are recorded therein, including three generations of ancestors and his brother's four children.  This was done in 1803.
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His baptism transcription:

First name(s)           John
Last name               Trotter
Baptism year            1758
Birth year              1758
Parish                  St Anne, Soho
County                  Middlesex
Country                 England
Father's first name(s)  John
Mother's first name(s)  Anne
Page                    164
Birth date              02 Feb 1758
Baptism date            28 Feb 1758
Archive                 City of Westminster Archives Centre
Record set              Westminster Baptisms

The actual entry was:

        February 1758
Born Baptism Bapt date
  2  John Trotter of John & Anne   28
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Death or burial not found.

Though the burial for a John Edward Trotter was found in Betchworth, Surrey in 1926 with the right birth year:

First name(s) JOHN EDWARD
Last name TROTTER
Birth year 1758
Death year 1826
Age 68
Burial year 1826
Burial day 17
Burial month 11
Place BETCHWORTH
Church description ST MICHAEL
Church denomination ANGLICAN
County Surrey
Country England
Record set National Burial Index for England & Wales

Or, in 1837:

First name(s) JOHN
Last name TROTTER
Gender Male
Death quarter 4
Death year 1837
District LAMBETH
County London
Volume 4
Page 247
Country England
Record set England & Wales deaths 1837-2007

or, in 1840:

First name(s) JOHN
Last name TROTTER
Gender Male
Death quarter 2
Death year 1840
District MIDHURST
County Sussex
Volume 7
Page 296
Country England
Record set England & Wales deaths 1837-2007
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That he was dead by 29 Jan 1846 is known from the fact that his wife was then recorded on PCC as a widow.  No will can be found for him in England.
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In March 1827 Robert Trotter of Hastings, Sussex administered the Death Duties for both John and Henry James Trotter.  Henry James looks very likely to have been that HJT who was son of JT and brother to RT, so I wonder if this gives a better clue to this John’s death date?
(Found on the Death Duty Registers on Find My Past.)

That not 100% reliable source, Burke’s Landed Gents has a record that Henry James died in 1830.
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Brian Bouchard wrote in on 14 Aug 2015 with this news:

“Eureka! I had identified a reference in a newspaper, under Cambridge,
to the death of John Trotter in his 68th year during 1826 but could not be
sure it referred to 'our' man. It turns out to have been him now found
brought from London for burial on 17/11/1826, aged 68, at Betchworth,
Surrey, - No 243 in the Register. No 614 records the interment of Jane
Sophia Trotter 81, 21/12/1845, from Twyford, Maresfield, Sussex.

“Why, you cry, Betchworth? Well it seems from the High Court case of Neilson
v Monro (decided in 1879) that Jane had inherited a moity interest in the
estate of Frances Dorothy Stables of Wonham following her death on
21/3/1832 -
https://books.google.co.uk/books?id=ULcHAAAAQAAJ&a...nepage&q=Frances%20Dorothy%20Stables%20%2B%20Wonham&f=false
- but there's probably more to the matter than that!”

This leads to the burial record of a John Edward Trotter:

First name(s) John Edward
Last name Trotter
Age 68
Birth year 1758
Death year 1826
Burial year 1826
Burial date 17 Nov 1826
Church St Michael
Denomination Anglican
Place Betchworth
County Surrey
Country England
Record set National Burial Index For England & Wales

While the age or birth year agrees with other information, I have not seen him described as ‘John Edward’ before, so a query remains on this finding.
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In March 1827, Robert Trotter was administrator for death duties for both these intestates: John Trotter (his father) and Henry James Trotter (his brother) and Robert was living at Hastings, Sussex.  The Death Duty index pointed to a record in Vol 1, Folio 154 for both these records.

This gives another steer towards John’s death date.

The TNA gives this information about their records of death duties:

“Death duty registers are in IR 26, with indexes in IR 27. Board papers dealing with the administration of the duties are in IR 62 and case books in IR 67. Specimens of death duty accounts are in IR 19, with selected death duty accounts of many persons well known in national life are in IR 59. Letters concerning contentious cases are in IR 6, with Scottish papers in IR 7. Reports to the Treasury on legacy duty cases are in IR 50. Copies of Wills, formerly in IR 5, were disposed of under the Public Records Act 1958 s6.”
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The recital in the prologue of his matriculations is:

“John Trotter of Shuddy Camps County of Cambridge Esquire, second lawful son of John Trotter of Kettleshiel in the County of Berwick and Horton in the County of Surrey Esquire, and Ann daughter of James Loch Esquire, which last John was the third and eldest surviving Son of Alexander Trotter of Kettleshiel Esquire ( Alexander and Robert, his two elder brothers having died unmarried) by Jean Second daughter of Sir Robert Steuart of Allanbank Baronet (a younger son of Sir James Steuart of Kirkfield and Coltness) by Jean Daughter of Sir John Gilmour of Craigmillar Lord President of the Court of Session by a daughter of Sir William Cockburn of Langton Baronet, which last mentioned Alexander Trotter of Kettleshiel Esquire descended of the antient family of Prentonan, . . .”

Matriculated by Lyon on 18th April 1803 for Trotter of Shuddy Camps, Cambs:

Argent a crescent Gules on a chief ingrailed Azure three mullets pierced of the field.

(Note the difference in the line of partition of the chief.)

Crest: A horse trotting proper.

Motto: Festina lente.
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By the College of Arms in the same year, this crest:

A dragon’s arm, Gules (I think).
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“An Ordinary of Scottish Arms, (Vol I)” by James Balfour Paul, pub 1893 by Wm Green & Sons, p. 57.  On 18th April 1803.

“Grantees of Arms” by the College of Arms, Vol II, by Joseph Foster edited by W Harry Rylands, pub 1917 in London for the Harleian Society, p. 371, referencing the College’s Registers, also 1803, vol XXII, fol 240.
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From a transcription of Faculty Office Marriage Licences:

First name(s) JOHN
Last name TROTTER
Licence year 1785
Licence date 06 Apr 1785
New calender date 06 Apr 1785
Bride's first name(s) Jane Sophia
Bride's last name DENT
Groom's first name(s) John
Groom's last name TROTTER
Place Dioceses of England & Wales
Record set Faculty Office Marriage Licences

A copy of the original has been ordered to give, hopefully, a view on where they were married.

Arrived and it says:

“6th April 1786

“Appeared personally John Trotter the younger Esquire and made oath that he is of the Parish of Saint george Bloomsbury in the County of Middlesex a Batchelor of the Ago of Twenty One and upwards.

“and intendeth to marry with Jane Sophia Dent of the Parish of Battersea in the County of Surry Spinster a minor of the Age of Twenty years and upwards but under the age of Twenty One yearsby and with the consent of Robert dent of he parish of battersea aforesaid Esquire the natural and lawful Father of the said Minor

“and that he knoweth of no lawful Impediment, by Reason of any Pre-contract, Consanguinity Affinity of any other lawful Means whatsoever, to hinder the said intended Marriage and prayed a Licence to solemnize the same in the parish Church of Saint George Bloomsbury aforesaid and further made oath that the usual place of Abode of him the said John Trotter hath been in the said parish of Saint George Bloomsbury aforesaid.

“for the space of four weeks last past.

“The appeared personally the said Robert Dent of the parish of battersea aforesaid Esquire and made Oath that he os the natural and lawful Father of the saidJane Sophia Dent ... the minor aforsaid and that he is willing ... the Solemnization of the above intended marriage.

“Sworn before me:
[Signed] Coller Ducarel
[and by] John Trotter jun,  Robt Dent”
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From the Gentleman’s magazine, Vol LV, Part I, for 1785, for the month of April 1785:
“April 7. Captain Trotter, of the 1st regt of dragoon guards, to Miss Dent.”
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