Search for ships by port rotation number

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This page is an index of ships by port rotation numbers drawn from the primary records of British shipping prior to 1855.

The registers of British seafarers for the period 1845 to 1854 are held at The National Archives (TNA) and show the person's career at sea, drawn from the crew lists of British ships. The registers use a code made up a port rotation number to identify the ship and a port number for the ship's port of registry. The key to the port numbers is known and this index to the port rotation numbers identifies the ship, so the crew lists can be found.

The crew lists are held at TNA in the series BT 98 in thousands of boxes (pieces) sorted by year, by port of registry and then by ship's name. Without the ship's name, there might be many pieces to search through, each holding up to 100 documents for many different ships.

This search page returns the ship's name with a list of the boxes of crew lists in BT 98 which are likely to hold the crew documents. It also provides links to the FamilySearch films which provide access to images of the documents.

Once the correct document has been found, the matching port rotation number is shown on it, thus completing the loop.

For full details of port rotation numbers, please follow this link: Port Rotation Numbers

How to search for ships by port rotation number

Enter the ship's port rotation number and select either the port name or number from one of the drop-down lists.

Then click .

Reading the results

The results show the ship's name and any data which has been extracted from BT 98, combined with other sources to provide details like registration entries and tonnages. We show the source of the data and if the main source is BT 98, we provide a link to TNA's catalogue.

Some data not found in BT 98 has been deduced from missing numbers. As explained in the full notes, Pete Owens discovered the underlying link between the Port Rotation numbers and the shipping registers for the port. That means that missing data can be deduced. For example, if port rotation numbers 195 and 199 for Whitby match with register entries 25/1840 and 29/1840, then port rotation number 197 would match with 27/1840, which can be identified from BT 162/19 as the ship Henry. We show the source of that data as 'Deduced from BT 98 and other sources'. We show how confident we are in this interpolation by a percentage, (Q) - 99% is best, down to 60% where there is a gap of twenty records.

We also provide links to other CLIP data for ships of that name. One link is for pre-1855 records; the other is for later years (but bear in mind that the ship may not have been extant by then).

Why does a search for a port rotation number fail?

Our data does not provide complete coverage.

We have gathered data from a 10% sample of the crew documents for the period 1845 to 1854 - all of those for 1851. Using the underlying pattern of the data which Pete Owens discovered, we have been able to fill in many of the gaps so the overall coverage is well over 60% and probably much higher for ships registered in the period up to 1851.

We are adding data to cover the period up to 1854 for the larger ports.

Beware! If you are using data from the seafarers' records, please bear in mind that it is often difficult to read the port rotation numbers. Do consider alternative readings and consider referring to newspaper records which may help to confirm which ships arrived or left around that date.

Using the results

Knowing the name of the ship, it is possible to work out which boxes at TNA might contain documents for the ship. We show that in the lower part of the page.

We use a colour code to show how sure we are that documents will be found, as shown in this table.

Be aware Apart from the years from which we have extracted data, there is no guarantee that documents will be found in any box, especially so where we have deduced the ship's name from other data. For some years, we can be fairly sure that the documents are not in that box, because they were not found there when data was extracted. We can not accept liability for the results of any inaccuracy in our data.

Please remember also that the data refers to the port rotation number - not to the ship's name. For example, if the ship was re-registered at the same port, there may well be documents for her after that date, but with a different port rotation number.

Where we have details of when the ship's registration at that port began and/or ended, we have used that to add comments about the years for which there are likely to be documents. For example, if the ship is shown in BT 162/19 as being re-registered in 1850, we will point out that there may be records for her in later years, but with a different port rotation number.

Colour codes for crew list sources
Documents have been found in this reference
Documents may be found in this reference
Documents were not found in this reference for port rotation number nnn
Documents will probably not be found in this reference for port rotation number nnn

There are two link icon buttons against each data item for the document sources:

  shows the TNA reference and provides a link to TNA's catalogue.

  shows the film reference and provides a link to the images on the FamilySearch site.

Be aware. You need an account with FamilySearch for this to work, and to be working from a FamilySearch centre or a FamilySearch Affiliate Library.

against a references indicates that crew name data from that reference is included in the name index (£) for the 1851 records in BT98 made by Family History Indexes.

Data sources

The data comes from a 10% sample of the crew lists in BT 98 for the period 1845 to 1854 - all of the documents for 1851. Most of the transcription was done using the FamilySearch films, working at FamilySearch Affiliate Libraries.

In parallel with gathering data from the crew lists, CLIP compiled indexes of ships pre-1855. One set is from BT 162/19 which lists ships extant in 1850 and the second is from parts of BT 111 which cover the period from the 1820s to 1855. This data is available separately here: Ships pre-1855 and Ships by port

The data from the crew lists was cross-checked during and after transcription by comparing it with data from BT 111 and BT 162, and also against the underlying links to the shipping registers on which the port rotation numbers were based.

Because of this tight cross-checking, the overall accuracy of the transcribed sample data is high - better than 95% - despite the fact that the documents themselves are hard to read and the Victorian clerks made errors (such as typos and confusing the registration dates for a ship). We were able to detect the errors and allow for them, generally by omitting the erroneous data.


The Port Rotation Number Project began when Peter Hamersley contacted CLIP in the summer of 2020 suggesting an index to the port rotation numbers. He has worked with us on the hard slog of extracting the data which makes it all work. We have been delighted to work with him in developing what is a major step forward in researching the crew documents held in BT 98.

We are most grateful to Bruno Pappalardo at TNA who has provided valuable support and assistance.

We thank our volunteer transcribers, Robert Holloway, Laura Hamersley and Janine Hamersley in Australia, Maxwell Crockett in NZ and Myfanwy Gate at the National Library of Wales (NLW). The staff of NLW have been most helpful.

Anglesey Archives have provided invaluable assistance by arranging for FamilySearch Affiliate Library status to provide CLIP with access to the records online.

Please chose the port number or port name

Port number :   

Port name :    

The Port Rotation Number Project began with the initiative of Peter Hamersley with whom we have been delighted to work in carrying through a ground-breaking project.

Click here to see a summary of the ports covered:

The table shows a list of the ports for which we have gathered port rotation number data. These are the columns:

the name of the port;
Port reference number
the reference number for that port, as used with the port rotation numbers;
PR numbers count
the count of port rotation numbers that we have found or deduced;
PR numbers min
the lowest port rotation number we have found;
PR numbers max
the highest port rotation number we have found;
the percentage of the port rotation numbers for this port which we have found, based on the previous numbers.

The percentage shown for each port is the coverage for ships registered in the period from the 1830s to 1854. Within that, for ships registered between 1845 and 1851, the coverage is mostly better than 90%.

We have completed the 400+ films for 1851. We are currently adding data from a sample of the 1854 crew lists for the larger ports. Our progress is shown here: Data progress

Port Port reference number PR numbers count PR number min PR number max %age
ABERDEEN 1 399269057
ABERYSTWYTH 2 2651635577
ALDEBURGH 3 2484563
ALLOA 113 112533733
ANSTRUTHER 4113649111
ARBROATH 115 210123688
ARUNDEL 4 531211153
AYR 5 61159674
BALLINA 122 212100
BALTIMORE 6 5982144
BANFF 7 2011328972
BARNSTAPLE 8 96919351
BEAUMARIS 9 2842860349
BELFAST 10 94543134072
BERWICK 11 78514256
BIDEFORD 12 1941836455
BRIDGWATER 15 187425673
BRIDLINGTON 16 1065420
BRIDPORT 17 22133884
BRISTOL 18 458472263
CAERNARFON 117 416452123652
CAMPBELTOWN 19 38147858
CARDIFF 20 831316653
CARDIGAN 21 282137176
CARLISLE 22 4327657
CARMARTHEN 116 2133563
CHEPSTOW 23 40289955
CHESTER 24 144822167
CHICHESTER 25 3588644
CLEY 26 139123559
COLCHESTER 27 2537653854
COLERAINE 28 522520
CORK 29 4283198944
COWES 30 203639552
DARTMOUTH 31 6382993270
DERBYHAVEN 148 572715843
DOUGLAS 147 934417570
DOVER 33 811221639
DROGHEDA 34 5427870
DUBLIN 35 5456186567
DUMFRIES 36 171123572
DUNBAR 60 1090293727
DUNDALK 37 29116255
DUNDEE 38 506181162
EXETER 39 245241359
FALMOUTH 40 1451323764
FAVERSHAM 41 214351741
FLEETWOOD 126 2412788
FOLKESTONE 123 811553
FOWEY 42 157721475
GAINSBOROUGH 110 2013951
GALWAY 43 21126538
GLASGOW 44 124632175772
GLOUCESTER 46 3451052966
GOOLE 47 632182376
GRANGEMOUTH 45 431010644
GREENOCK 48 480893851
GRIMSBY 49 7459878
GUERNSEY 151 184331558
GWEEK 50 571462
HARTLEPOOL 118 231123598
HARWICH 51 129421062
HASTINGS 84 2811118636
HULL 52 5151193855
INVERNESS 54 2673450656
IPSWICH 55 2522445558
IRVINE 56 162226960
JERSEY 152 5062588258
KIRKCALDY 57 832128631
KIRKCUDBRIGHT 36 1924428545
KIRKWALL 58 551311951
LANCASTER 59 94917655
LEITH 60 258152649
LERWICK 61 193811823
LIMERICK 67 911722244
LIVERPOOL 62 40461612666
LLANELLI 63 67815744
LONDON 64 489718917153
LONDONDERRY 65 5538764
LYME 66 1913063
LYNN 68 265438469
MALDON 69 164328857
MARYPORT 112 139425056
MILFORD 70 166327560
MONTROSE 71 157233247
NEWCASTLE 75 17036306055
NEWHAVEN 74 2184260
NEWPORT 72 109718361
NEWRY 73 1383831749
PADSTOW 76 162522075
PEEL 149 42135176100
PENZANCE 77 1133818476
PERTH 114 89519147
PETERHEAD 127 63986105688
PLYMOUTH 78 444580055
POOLE 79 131424953
PORT GLASGOW 81 701416645
PORTSMOUTH 80 2382462839
PRESTON 109 1721228063
PWLLHELI 117 24056184983
RAMSEY 150 4019327150
RAMSGATE 82 1242132440
ROCHESTER 83 3133763452
ROSS 111 4646771
RUNCORN 120 5436388
RYE 84 991337227
SCARBOROUGH 85 225134864
SCILLY 86 851212673
SHIELDS 124 14021158788
SHOREHAM 88 1482422872
SLIGO 89 2527633
SOUTHAMPTON 90 281948958
SOUTHWOLD 91 1453742
ST IVES 87 193827671
ST JOHN, NEW BRUNSWICK 230 30951153820
STOCKTON 93 189964229
STORNOWAY 94 32810233
STRANGFORD 125 5716291
STRANRAER 95 3617548
SUNDERLAND 92 21811431050
SWANSEA 96 2203938962
TRALEE 119 371727
TRURO 97 3958349
WATERFORD 98 226335663
WELLS 99 3143450046
WEXFORD 102 127721062
WEYMOUTH 101 101217358
WHITBY 104 765197678
WHITEHAVEN 103 264167838
WICK 105 42179453
WIGTOWN 121 9036248175
WISBECH 106 143220470
WOODBRIDGE 107 4948956
WORKINGTON 128 1362753526
YARMOUTH 108 83412131064