# November 2025

## OSMM Topography Layer product count

The following table contains product counts for this release of OSMM Topography Layer data. The dates shown are extraction dates, not release dates.

| OSMM Topography Layer                | Count on 25/09/2025 (Last Release) | Count on 06/11/2025 (This Release) |
| ------------------------------------ | ---------------------------------- | ---------------------------------- |
| **Total Feature Count**              | **515 614 618**                    | **516 255 739**                    |
| Count of Topo Area                   | 129 018 023                        | 129 179 335                        |
| Count of Topo Line                   | 355 475 070                        | 355 932 638                        |
| Count of Topo Point                  | 4 455 077                          | 4 462 725                          |
| Count of Topo Bline                  | 520 905                            | 520 570                            |
| Count of Topo CartoSym               | 3 845 014                          | 3 854 066                          |
| Count of Topo CartoTxt               | 22 300 529                         | 22 306 405                         |
| **Total Count of Deletes**           | **727 014**                        | **836 866**                        |
| Count of Topo Area deletions         | 135 551                            | 162 006                            |
| Count of Topo Line deletions         | 530 546                            | 612 392                            |
| Count of Topo Point deletions        | 6 315                              | 6 892                              |
| Count of Topo Bline deletions        | 2 034                              | 943                                |
| Count of Topo CartoSym deletions     | 7 229                              | 5 155                              |
| Count of Topo CartoTxt deletions     | 45 339                             | 49 478                             |
| **Total Count of Inserts**           | **1 366 855**                      | **1 477 987**                      |
| Count of Topo Area inserts           | 296 253                            | 323 318                            |
| Count of Topo Line inserts           | 986 399                            | 1 069 960                          |
| Count of Topo Point inserts          | 18 654                             | 14 540                             |
| Count of Topo Bline inserts          | 605                                | 608                                |
| Count of Topo CartoSym inserts       | 19 475                             | 14 207                             |
| Count of Topo CartoTxt inserts       | 45 474                             | 55 354                             |
| **Total Count of Modifications**     | **1 274 983**                      | **1 407 831**                      |
| Count of Topo Area Modifications     | 635 899                            | 715 622                            |
| Count of Topo Line Modifications     | 620 168                            | 673 769                            |
| Count of Topo Point Modifications    | 1 177                              | 1 110                              |
| Count of Topo Bline Modifications    | 2 063                              | 1 450                              |
| Count of Topo CartoSym Modifications | 66                                 | 54                                 |
| Count of Topo CartoTxt Modifications | 15 610                             | 15 826                             |
| **COU Size (bytes)**                 | **511 583 092**                    | **625 627 136**                    |

## Changed TOIDs

Numerous TOIDs (Topographic Identifiers) have changed since the last refresh, resulting in a visual difference in the data. The list below shows a sample of changed TOIDs and their locations that you can use as 'lookup samples' to validate that your latest supply has updated correctly:

| TOID                 | Location (i.e. XY Coordinates) |
| -------------------- | ------------------------------ |
| osgb5000005333266045 | 329288.91, 667878.807          |
| osgb5000005225411653 | 335284.33, 445332.88           |
| osgb5000005316042299 | 615133.243, 305804.265         |
| osgb5000005324924136 | 140963.498, 831364.515         |
| osgb1000000222715645 | 322651.151, 476807.838         |
| osgb5000005200470167 | 584183.128, 345730.459         |

## Discrepancies <a href="#hlk115182660" id="hlk115182660"></a>

In this release 25 errors were detected, of which 25 are new errors. These are all considered to be minor errors and there are no major errors present.

We aim to have all errors resolved prior to the next release as part of ongoing quality improvements.

## Next release

The next release of OS MasterMap Topography Layer is scheduled for **05 January 2026**.&#x20;


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