{ "page": "compare", "query": { "a": "VMBS", "b": "VBTLX" }, "retrieved_at": "2026-07-07T18:20:05+00:00", "disclaimer": "Informational only — not investment advice. FundWatcher presents publicly available data and makes no recommendation to buy or sell any security. Verify all figures against the source filing before relying on them.", "attribution": "Data sourced from U.S. SEC EDGAR filings (Forms N-PORT, N-CEN, and prospectus Risk/Return summaries). FundWatcher is not affiliated with the SEC.", "terms": { "notice": "Use of this data is subject to the FundWatcher Terms of Service. Information may be used only for personal, non-commercial research and may not be redistributed.", "url": "https://fundwatcher.app/terms/" }, "fund_a": { "name": "VANGUARD MORTGAGE-BACKED SECURITIES INDEX FUND", "ticker": "VMBS", "slug": "VMBS", "series_id": "S000026865", "html_url": "https://fundwatcher.app/funds/VMBS/" }, "fund_b": { "name": "VANGUARD TOTAL BOND MARKET INDEX FUND", "ticker": "VBTLX", "slug": "VBTLX", "series_id": "S000002564", "html_url": "https://fundwatcher.app/funds/VBTLX/" }, "overlap": { "coverage_a_by_b": "0.1668667048106495302571404350", "coverage_b_by_a": "0.1668667048106495302571404350", "shared_count": 3539, "as_of": { "a": "2026-02-28", "b": "2026-03-31" }, "a_top": [ { "name": "Vanguard Market Liquidity Fund", "value": "774216161.24", "weight": "0.04428236", "shared": true }, { "name": "G2SF 5 3/25", "value": "74591314.55", "weight": "0.00426635", "shared": false }, { "name": "Uniform Mortgage-Backed Security, TBA", "value": "73598943.57", "weight": "0.00420959", "shared": false }, { "name": "Uniform Mortgage-Backed Security, TBA", "value": "57306001.51", "weight": "0.00327770", "shared": false }, { "name": "FNCL 5 3/24", "value": "53664065.77", "weight": "0.00306939", "shared": false }, { "name": "G2 MB0936", "value": "49314818.35", "weight": "0.00282063", "shared": true }, { "name": "FR SD4155", "value": "49022410.47", "weight": "0.00280390", "shared": false }, { "name": "G2 MB0025", "value": "46671931.05", "weight": "0.00266947", "shared": true }, { "name": "FR SD8146", "value": "46056718.25", "weight": "0.00263428", "shared": true }, { "name": "FNCL 5.5 3/25", "value": "43495927.30", "weight": "0.00248781", "shared": false }, { "name": "FR SD8128", "value": "41604864.55", "weight": "0.00237965", "shared": true }, { "name": "FN MA4325", "value": "41263506.56", "weight": "0.00236012", "shared": true }, { "name": "G2 MA8347", "value": "39386327.79", "weight": "0.00225276", "shared": true }, { "name": "G2 MA7311", "value": "38282863.75", "weight": "0.00218964", "shared": true }, { "name": "G2 MB0624", "value": "37940856.26", "weight": "0.00217008", "shared": true }, { "name": "FR SD8106", "value": "37524645.22", "weight": "0.00214627", "shared": true }, { "name": "Uniform Mortgage-Backed Security, TBA", "value": "36645969.39", "weight": "0.00209602", "shared": false }, { "name": "G2 MA7135", "value": "36285167.46", "weight": "0.00207538", "shared": true }, { "name": "FR SD8134", "value": "36205619.72", "weight": "0.00207083", "shared": true }, { "name": "G2 MA7826", "value": "35217230.83", "weight": "0.00201430", "shared": true }, { "name": "FR SD8121", "value": "35160691.36", "weight": "0.00201106", "shared": true }, { "name": "G2 MA6994", "value": "35154866.88", "weight": "0.00201073", "shared": true }, { "name": "FN FS1560", "value": "35146808.88", "weight": "0.00201027", "shared": false }, { "name": "FR RQ0028", "value": "33637064.95", "weight": "0.00192392", "shared": true }, { "name": "Uniform Mortgage-Backed Security, TBA", "value": "33038867.24", "weight": "0.00188970", "shared": false }, { "name": "FN MA4378", "value": "32983195.50", "weight": "0.00188652", "shared": true }, { "name": "FR SD8506", "value": "32943691.80", "weight": "0.00188426", "shared": true }, { "name": "FN MA4305", "value": "32741456.09", "weight": "0.00187269", "shared": true }, { "name": "G2 MB0024", "value": "32665864.51", "weight": "0.00186837", "shared": true }, { "name": "G2 MA8267", "value": "32403431.22", "weight": "0.00185336", "shared": true }, { "name": "G2 MB0485", "value": "31888225.09", "weight": "0.00182389", "shared": true }, { "name": "FR SD8177", "value": "31818019.19", "weight": "0.00181988", "shared": true }, { "name": "FR SD1507", "value": "31522336.07", "weight": "0.00180296", "shared": true }, { "name": "FN MA4119", "value": "31386000.04", "weight": "0.00179517", "shared": true }, { "name": "FN MA4255", "value": "30627029.62", "weight": "0.00175175", "shared": true }, { "name": "FR SD8493", "value": "30562728.79", "weight": "0.00174808", "shared": true }, { "name": "G2 MA7471", "value": "30175239.04", "weight": "0.00172591", "shared": true }, { "name": "FR SD8182", "value": "29337187.92", "weight": "0.00167798", "shared": true }, { "name": "G2 MB0091", "value": "28751443.87", "weight": "0.00164448", "shared": true }, { "name": "FN MA4600", "value": "28741948.36", "weight": "0.00164394", "shared": true }, { "name": "G2 MB0146", "value": "28741810.39", "weight": "0.00164393", "shared": true }, { "name": "FR SD8463", "value": "28407277.79", "weight": "0.00162479", "shared": true }, { "name": "G2 MA9605", "value": "28187874.97", "weight": "0.00161224", "shared": true }, { "name": "FR SD8474", "value": "27863459.95", "weight": "0.00159369", "shared": true }, { "name": "FN FS5129", "value": "27386261.58", "weight": "0.00156639", "shared": true }, { "name": "G2 MB0365", "value": "27351026.84", "weight": "0.00156438", "shared": true }, { "name": "G2 MB0092", "value": "27249751.12", "weight": "0.00155859", "shared": true }, { "name": "FR SD8155", "value": "27093150.25", "weight": "0.00154963", "shared": true }, { "name": "FN MA5445", "value": "26989378.07", "weight": "0.00154369", "shared": true }, { "name": "FN MA4437", "value": "26927970.70", "weight": "0.00154018", "shared": true } ], "b_top": [ { "name": "Vanguard Market Liquidity Fund", "value": "4124925631.68", "weight": "0.01068457", "shared": true }, { "name": "US TREASURY N/B", "value": "1852642634.81", "weight": "0.00479880", "shared": false }, { "name": "US TREASURY N/B", "value": "1625683460.43", "weight": "0.00421092", "shared": false }, { "name": "US TREASURY N/B", "value": "1624465195.94", "weight": "0.00420776", "shared": false }, { "name": "US TREASURY N/B", "value": "1618787409.42", "weight": "0.00419306", "shared": false }, { "name": "US TREASURY N/B", "value": "1603500406.19", "weight": "0.00415346", "shared": false }, { "name": "US TREASURY N/B", "value": "1594278794.54", "weight": "0.00412957", "shared": false }, { "name": "US TREASURY N/B", "value": "1564023956.70", "weight": "0.00405120", "shared": false }, { "name": "US TREASURY N/B", "value": "1525021463.81", "weight": "0.00395018", "shared": false }, { "name": "US TREASURY N/B", "value": "1518506883.58", "weight": "0.00393330", "shared": false }, { "name": "US TREASURY N/B", "value": "1408995913.48", "weight": "0.00364964", "shared": false }, { "name": "US TREASURY N/B", "value": "1403754623.53", "weight": "0.00363607", "shared": false }, { "name": "US TREASURY N/B", "value": "1402580516.78", "weight": "0.00363303", "shared": false }, { "name": "US TREASURY N/B", "value": "1362247523.84", "weight": "0.00352855", "shared": false }, { "name": "US TREASURY N/B", "value": "1361897728.34", "weight": "0.00352765", "shared": false }, { "name": "US TREASURY N/B", "value": "1354619681.00", "weight": "0.00350880", "shared": false }, { "name": "US TREASURY N/B", "value": "1321607257.67", "weight": "0.00342329", "shared": false }, { "name": "US TREASURY N/B", "value": "1275635310.00", "weight": "0.00330421", "shared": false }, { "name": "US TREASURY N/B", "value": "1252754033.20", "weight": "0.00324494", "shared": false }, { "name": "US TREASURY N/B", "value": "1250636252.76", "weight": "0.00323945", "shared": false }, { "name": "US TREASURY N/B", "value": "1248984033.08", "weight": "0.00323517", "shared": false }, { "name": "US TREASURY N/B", "value": "1237980821.57", "weight": "0.00320667", "shared": false }, { "name": "US TREASURY N/B", "value": "1230596061.57", "weight": "0.00318754", "shared": false }, { "name": "US TREASURY N/B", "value": "1222523448.90", "weight": "0.00316663", "shared": false }, { "name": "US TREASURY N/B", "value": "1203357610.31", "weight": "0.00311699", "shared": false }, { "name": "US TREASURY N/B", "value": "1191325241.24", "weight": "0.00308582", "shared": false }, { "name": "US TREASURY N/B", "value": "1113834878.18", "weight": "0.00288510", "shared": false }, { "name": "US TREASURY N/B", "value": "1061976585.82", "weight": "0.00275078", "shared": false }, { "name": "US TREASURY N/B", "value": "1060235601.47", "weight": "0.00274627", "shared": false }, { "name": "US TREASURY N/B", "value": "1051904525.91", "weight": "0.00272469", "shared": false }, { "name": "US TREASURY N/B", "value": "1004477740.58", "weight": "0.00260184", "shared": false }, { "name": "US TREASURY N/B", "value": "937414850.54", "weight": "0.00242813", "shared": false }, { "name": "US TREASURY N/B", "value": "934802670.40", "weight": "0.00242137", "shared": false }, { "name": "US TREASURY N/B", "value": "932396788.41", "weight": "0.00241514", "shared": false }, { "name": "US TREASURY N/B", "value": "931043269.36", "weight": "0.00241163", "shared": false }, { "name": "US TREASURY N/B", "value": "927075406.22", "weight": "0.00240135", "shared": false }, { "name": "US TREASURY N/B", "value": "924208262.64", "weight": "0.00239393", "shared": false }, { "name": "US TREASURY N/B", "value": "923588845.86", "weight": "0.00239232", "shared": false }, { "name": "US TREASURY N/B", "value": "911077318.13", "weight": "0.00235991", "shared": false }, { "name": "US TREASURY N/B", "value": "910228103.65", "weight": "0.00235771", "shared": false }, { "name": "US TREASURY N/B", "value": "899692297.90", "weight": "0.00233042", "shared": false }, { "name": "US TREASURY N/B", "value": "892733225.41", "weight": "0.00231240", "shared": false }, { "name": "US TREASURY N/B", "value": "885903077.98", "weight": "0.00229471", "shared": false }, { "name": "US TREASURY N/B", "value": "882695584.69", "weight": "0.00228640", "shared": false }, { "name": "US TREASURY N/B", "value": "881856536.30", "weight": "0.00228422", "shared": false }, { "name": "US TREASURY N/B", "value": "878753508.06", "weight": "0.00227619", "shared": false }, { "name": "US TREASURY N/B", "value": "877047509.89", "weight": "0.00227177", "shared": false }, { "name": "US TREASURY N/B", "value": "871110309.24", "weight": "0.00225639", "shared": false }, { "name": "US TREASURY N/B", "value": "866489207.97", "weight": "0.00224442", "shared": false }, { "name": "US TREASURY N/B", "value": "864619049.38", "weight": "0.00223957", "shared": false } ] }, "error": null, "sources": [ { "label": "N-PORT (fund A)", "accession_no": "0001021882-26-000290", "as_of": "2026-02-28", "edgar_url": "https://www.sec.gov/Archives/edgar/data/1021882/000102188226000290/0001021882-26-000290-index.htm" }, { "label": "N-PORT (fund B)", "accession_no": "0000794105-26-000185", "as_of": "2026-03-31", "edgar_url": "https://www.sec.gov/Archives/edgar/data/794105/000079410526000185/0000794105-26-000185-index.htm" } ] }