# February 2026 ## 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.

OS MM Topography Layer	Count on 11/12/2025 (Last Release)	TextCount on 29/01/2026 (This Release)
Total Feature Count	516 731 189	517 279 866
Count of Topo Area	129 299 175	129 436 199
Count of Topo Line	356 273 836	356 666 805
Count of Topo Point	4 466 384	4 469 251
Count of Topo Bline	520 602	520 431
Count of Topo CartoSym	3 859 375	3 859 805
Count of Topo CartoTxt	22 311 817	22 327 375
Total Count of Deletes	598 529	678 764
Count of Topo Area deletions	113 839	134 834
Count of Topo Line deletions	437 808	492 827
Count of Topo Point deletions	4 995	3 157
Count of Topo Bline deletions	281	527
Count of Topo CartoSymcc deletions	2 984	2 983
Count of Topo CartoTxtcc deletions	38 622	44 436
Total Count of Inserts	1 073 979	1 227 441
Count of Topo Area inserts	233 679	271 858
Count of Topo Line inserts	779 006	885 796
Count of Topo Point inserts	8 654	6 024
Count of Topo Bline inserts	313	356
Count of Topo CartoSym inserts	8 293	3 413
Count of Topo CartoTxt inserts	44 034	59 994
Total Count of Modifications	1 038 366	1 158 022
Count of Topo Area Modifications	527 931	590 892
Count of Topo Line Modifications	496 225	549 034
Count of Topo Point Modifications	1 161	402
Count of Topo Bline Modifications	404	611
Count of Topo CartoSym Modifications	151	32
Count of Topo CartoTxt Modifications	12 494	17 051
COU Size (bytes)	464 904 192	514 400 256

## 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) | | -------------------- | ------------------------------ | | osgb1000000288795323 | 238523.656 921440.485 | | osgb1000034193828 | 271625.8 331824.9 | | osgb1000000083109971 | 495166.8 484212.1 | | osgb1000000288009704 | 203104.4 907457.1 | | osgb1000002092953297 | 276099.423 207624.585 | | osgb5000005243347366 | 393168.73 459052.754 | ## Discrepancies In this release 40 errors were detected, of which, 15 have existed since the previous refresh. 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 **30 March 2026.** --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.os.uk/os-downloads/products/maps-and-imagery-portfolio/os-mastermap-topography-layer/release-notes/february-2026.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.