diff --git a/WalletWasabi.Backend/Global.cs b/WalletWasabi.Backend/Global.cs
index 3b183259bc6..80e6c34f044 100644
--- a/WalletWasabi.Backend/Global.cs
+++ b/WalletWasabi.Backend/Global.cs
@@ -42,7 +42,7 @@ public Global(string dataDir, IRPCClient rpcClient, Config config)
 
 		// Initialize index building
 		var indexBuilderServiceDir = Path.Combine(DataDir, "IndexBuilderService");
-		var indexFilePath = Path.Combine(indexBuilderServiceDir, $"Index{RpcClient.Network}.dat");
+		var indexFilePath = Path.Combine(indexBuilderServiceDir, $"Index{RpcClient.Network}.sqlite");
 		IndexBuilderService = new(RpcClient, HostedServices.Get<BlockNotifier>(), indexFilePath);
 	}
 
diff --git a/WalletWasabi.Tests/UnitTests/BitcoinCore/IndexBuilderServiceTests.cs b/WalletWasabi.Tests/UnitTests/BitcoinCore/IndexBuilderServiceTests.cs
index 1b8f80f23fa..196a2fb695f 100644
--- a/WalletWasabi.Tests/UnitTests/BitcoinCore/IndexBuilderServiceTests.cs
+++ b/WalletWasabi.Tests/UnitTests/BitcoinCore/IndexBuilderServiceTests.cs
@@ -28,13 +28,14 @@ public async Task SegwitTaprootUnsynchronizedBitcoinNodeAsync()
 			}),
 		};
 		using var blockNotifier = new BlockNotifier(rpc);
-		var indexer = new IndexBuilderService(rpc, blockNotifier, "filters.txt");
+		var indexer = new IndexBuilderService(rpc, blockNotifier, "filters.sqlite");
 
 		indexer.Synchronize();
 
 		await Task.Delay(TimeSpan.FromSeconds(1));
 		//// Assert.False(indexer.IsRunning);     // <------------ ERROR: it should have stopped but there is a bug for RegTest
-		Assert.Throws<ArgumentOutOfRangeException>(() => indexer.GetLastFilter());  // There are no filters
+		// There is only starting filter
+		Assert.True(indexer.GetLastFilter()?.Header.BlockHash.Equals(StartingFilters.GetStartingFilter(rpc.Network).Header.BlockHash));
 	}
 
 	[Fact]
@@ -55,13 +56,14 @@ public async Task SegwitTaprootStalledBitcoinNodeAsync()
 			}
 		};
 		using var blockNotifier = new BlockNotifier(rpc);
-		var indexer = new IndexBuilderService(rpc, blockNotifier, "filters.txt");
+		var indexer = new IndexBuilderService(rpc, blockNotifier, "filters.sqlite");
 
 		indexer.Synchronize();
 
 		await Task.Delay(TimeSpan.FromSeconds(2));
 		Assert.True(indexer.IsRunning);  // It is still working
-		Assert.Throws<ArgumentOutOfRangeException>(() => indexer.GetLastFilter());  // There are no filters
+		// There is only starting filter
+		Assert.True(indexer.GetLastFilter()?.Header.BlockHash.Equals(StartingFilters.GetStartingFilter(rpc.Network).Header.BlockHash));
 		Assert.True(called > 1);
 	}
 
@@ -94,7 +96,7 @@ public async Task SegwitTaprootSynchronizingBitcoinNodeAsync()
 		Assert.True(indexer.IsRunning);  // It is still working
 
 		var lastFilter = indexer.GetLastFilter();
-		Assert.Equal(9, (int)lastFilter.Header.Height);
+		Assert.Equal(9, (int)lastFilter!.Header.Height);
 		Assert.True(called > 1);
 	}
 
@@ -182,13 +184,14 @@ public async Task TaprootUnsynchronizedBitcoinNodeAsync()
 			}),
 		};
 		using var blockNotifier = new BlockNotifier(rpc);
-		var indexer = new IndexBuilderService(rpc, blockNotifier, "filters.txt");
+		var indexer = new IndexBuilderService(rpc, blockNotifier, "filters.sqlite");
 
 		indexer.Synchronize();
 
 		await Task.Delay(TimeSpan.FromSeconds(1));
 		//// Assert.False(indexer.IsRunning);     // <------------ ERROR: it should have stopped but there is a bug for RegTest
-		Assert.Throws<ArgumentOutOfRangeException>(() => indexer.GetLastFilter());  // There are no filters
+		// There is only starting filter
+		Assert.True(indexer.GetLastFilter()?.Header.BlockHash.Equals(StartingFilters.GetStartingFilter(rpc.Network).Header.BlockHash));
 	}
 
 	[Fact]
@@ -209,13 +212,14 @@ public async Task TaprootStalledBitcoinNodeAsync()
 			}
 		};
 		using var blockNotifier = new BlockNotifier(rpc);
-		var indexer = new IndexBuilderService(rpc, blockNotifier, "filters.txt");
+		var indexer = new IndexBuilderService(rpc, blockNotifier, "filters.sqlite");
 
 		indexer.Synchronize();
 
 		await Task.Delay(TimeSpan.FromSeconds(2));
 		Assert.True(indexer.IsRunning);  // It is still working
-		Assert.Throws<ArgumentOutOfRangeException>(() => indexer.GetLastFilter());  // There are no filters
+		// There is only starting filter
+		Assert.True(indexer.GetLastFilter()?.Header.BlockHash.Equals(StartingFilters.GetStartingFilter(rpc.Network).Header.BlockHash));
 		Assert.True(called > 1);
 	}
 
@@ -248,7 +252,7 @@ public async Task TaprootSynchronizingBitcoinNodeAsync()
 		Assert.True(indexer.IsRunning);  // It is still working
 
 		var lastFilter = indexer.GetLastFilter();
-		Assert.Equal(9, (int)lastFilter.Header.Height);
+		Assert.Equal(9, (int)lastFilter!.Header.Height);
 		Assert.True(called > 1);
 	}
 
diff --git a/WalletWasabi/Blockchain/BlockFilters/IndexBuilderService.cs b/WalletWasabi/Blockchain/BlockFilters/IndexBuilderService.cs
index 087a3b157b5..cf663557aa6 100644
--- a/WalletWasabi/Blockchain/BlockFilters/IndexBuilderService.cs
+++ b/WalletWasabi/Blockchain/BlockFilters/IndexBuilderService.cs
@@ -1,10 +1,10 @@
 using NBitcoin;
 using System.Collections.Generic;
-using System.Collections.Immutable;
 using System.IO;
 using System.Linq;
 using System.Threading;
 using System.Threading.Tasks;
+using Microsoft.Data.Sqlite;
 using WalletWasabi.Backend.Models;
 using WalletWasabi.BitcoinCore.Rpc;
 using WalletWasabi.BitcoinCore.Rpc.Models;
@@ -12,6 +12,7 @@
 using WalletWasabi.Helpers;
 using WalletWasabi.Logging;
 using WalletWasabi.Models;
+using WalletWasabi.Stores;
 
 namespace WalletWasabi.Blockchain.BlockFilters;
 
@@ -41,31 +42,12 @@ public IndexBuilderService(IRPCClient rpc, BlockNotifier blockNotifier, string i
 
 		IoHelpers.EnsureContainingDirectoryExists(IndexFilePath);
 
-		// Testing permissions.
-		using (var _ = File.Open(IndexFilePath, FileMode.OpenOrCreate, FileAccess.ReadWrite))
+		if (RpcClient.Network == Network.RegTest && File.Exists(IndexFilePath))
 		{
+			File.Delete(IndexFilePath); // RegTest is not a global ledger, better to delete it.
 		}
 
-		if (File.Exists(IndexFilePath))
-		{
-			if (RpcClient.Network == Network.RegTest)
-			{
-				File.Delete(IndexFilePath); // RegTest is not a global ledger, better to delete it.
-			}
-			else
-			{
-				ImmutableList<FilterModel>.Builder builder = ImmutableList.CreateBuilder<FilterModel>();
-
-				foreach (var line in File.ReadAllLines(IndexFilePath))
-				{
-					var filter = FilterModel.FromLine(line);
-					builder.Add(filter);
-				}
-
-				Index = builder.ToImmutableList();
-			}
-		}
-
+		IndexStorage = CreateBlockFilterSqliteStorage();
 		BlockNotifier.OnBlock += BlockNotifier_OnBlock;
 	}
 
@@ -74,7 +56,7 @@ public IndexBuilderService(IRPCClient rpc, BlockNotifier blockNotifier, string i
 	private IRPCClient RpcClient { get; }
 	private BlockNotifier BlockNotifier { get; }
 	private string IndexFilePath { get; }
-	private ImmutableList<FilterModel> Index { get; set; } = ImmutableList<FilterModel>.Empty;
+	private BlockFilterSqliteStorage IndexStorage { get; set; }
 
 	/// <remarks>Guards <see cref="Index"/>.</remarks>
 	private object IndexLock { get; } = new();
@@ -85,6 +67,21 @@ public IndexBuilderService(IRPCClient rpc, BlockNotifier blockNotifier, string i
 
 	private RpcPubkeyType[] PubKeyTypes { get; } = [RpcPubkeyType.TxWitnessV0Keyhash, RpcPubkeyType.TxWitnessV1Taproot];
 
+	private BlockFilterSqliteStorage CreateBlockFilterSqliteStorage()
+	{
+		try
+		{
+			return BlockFilterSqliteStorage.FromFile(dataSource: IndexFilePath, startingFilter: StartingFilters.GetStartingFilter(RpcClient.Network));
+		}
+		catch (SqliteException ex) when (ex.SqliteExtendedErrorCode == 11) // 11 ~ SQLITE_CORRUPT error code
+		{
+			Logger.LogError($"Failed to open SQLite storage file because it's corrupted. Deleting the storage file '{IndexFilePath}'.");
+
+			File.Delete(IndexFilePath);
+			throw;
+		}
+	}
+
 	public static GolombRiceFilter CreateDummyEmptyFilter(uint256 blockHash)
 	{
 		return new GolombRiceFilterBuilder()
@@ -127,14 +124,11 @@ public void Synchronize()
 						{
 							SyncInfo syncInfo = await GetSyncInfoAsync().ConfigureAwait(false);
 
-							FilterModel? lastIndexFilter = null;
+							FilterModel? lastIndexFilter;
 
 							lock (IndexLock)
 							{
-								if (Index.Count != 0)
-								{
-									lastIndexFilter = Index[^1];
-								}
+								lastIndexFilter = GetLastFilter();
 							}
 
 							uint currentHeight;
@@ -190,7 +184,7 @@ public void Synchronize()
 							{
 								Logger.LogWarning("Reorg observed on the network.");
 
-								await ReorgOneAsync().ConfigureAwait(false);
+								ReorgOne();
 
 								// Skip the current block.
 								continue;
@@ -201,11 +195,9 @@ public void Synchronize()
 							var smartHeader = new SmartHeader(block.Hash, block.PrevBlockHash, nextHeight, block.BlockTime);
 							var filterModel = new FilterModel(smartHeader, filter);
 
-							await File.AppendAllLinesAsync(IndexFilePath, new[] { filterModel.ToLine() }).ConfigureAwait(false);
-
 							lock (IndexLock)
 							{
-								Index = Index.Add(filterModel);
+								IndexStorage.TryAppend(filterModel);
 							}
 
 							// If not close to the tip, just log debug.
@@ -289,22 +281,15 @@ private static List<Script> FetchScripts(VerboseBlockInfo block, RpcPubkeyType[]
 		return scripts;
 	}
 
-	private async Task ReorgOneAsync()
+	private void ReorgOne()
 	{
-		// 1. Rollback index.
-		uint256 blockHash;
-
 		lock (IndexLock)
 		{
-			blockHash = Index[^1].Header.BlockHash;
-			Index = Index.RemoveAt(Index.Count - 1);
+			if(IndexStorage.TryRemoveLast(out var removedFilter))
+			{
+				Logger.LogInfo($"REORG invalid block: {removedFilter.Header.BlockHash}");
+			}
 		}
-
-		Logger.LogInfo($"REORG invalid block: {blockHash}");
-
-		// 2. Serialize Index. (Remove last line.)
-		var lines = await File.ReadAllLinesAsync(IndexFilePath).ConfigureAwait(false);
-		await File.WriteAllLinesAsync(IndexFilePath, lines.Take(lines.Length - 1).ToArray()).ConfigureAwait(false);
 	}
 
 	private async Task<SyncInfo> GetSyncInfoAsync()
@@ -329,50 +314,37 @@ private void BlockNotifier_OnBlock(object? sender, Block e)
 
 	public (Height bestHeight, IEnumerable<FilterModel> filters) GetFilterLinesExcluding(uint256 bestKnownBlockHash, int count, out bool found)
 	{
-		found = false; // Only build the filter list from when the known hash is found.
-		var filters = new List<FilterModel>();
-
-		ImmutableList<FilterModel> currentIndex;
-
 		lock (IndexLock)
 		{
-			currentIndex = Index;
-		}
-
-		if (currentIndex.Count == 0)
-		{
-			return (Height.Unknown, []);
-		}
-
-		// Search for bestKnownBlockHash from last to first
-		var i = currentIndex.Count - 1;
-		for (; i >= 0; i--)
-		{
-			if (!currentIndex[i].Header.BlockHash.Equals(bestKnownBlockHash))
+			var filterModels = IndexStorage.FetchNewerThanBlockHash(bestKnownBlockHash, count).ToList();
+			uint bestHeight;
+			if (filterModels.Count > 0)
 			{
-				continue;
+				bestHeight = (uint)IndexStorage.GetBestHeight();
+				found = true;
 			}
+			else
+			{
+				var lastFilter = GetLastFilter();
+				if (lastFilter is null)
+				{
+					found = false;
+					return (new Height(HeightType.Unknown), []);
+				}
 
-			found = true;
-			break;
-		}
-
-		if (found && i < currentIndex.Count - 1)
-		{
-			// Populate filters starting from the found index + 1
-			var startIndex = i + 1;
-			var filtersCount = Math.Min(count, currentIndex.Count - startIndex);
-			filters.AddRange(currentIndex.GetRange(startIndex, filtersCount));
+				found = lastFilter.Header.BlockHash == bestKnownBlockHash;
+				bestHeight = lastFilter.Header.Height;
+			}
+			return (new Height(bestHeight), filterModels);
 		}
-
-		return (new Height(currentIndex[^1].Header.Height), filters);
 	}
 
-	public FilterModel GetLastFilter()
+	public FilterModel? GetLastFilter()
 	{
 		lock (IndexLock)
 		{
-			return Index[^1];
+			var lastFilterList = IndexStorage.FetchLast(1).ToList();
+			return lastFilterList.Count == 0 ? null : lastFilterList[0];
 		}
 	}
 
diff --git a/WalletWasabi/Stores/BlockFilterSqliteStorage.cs b/WalletWasabi/Stores/BlockFilterSqliteStorage.cs
index 8d8c42574be..d3c29eeff4b 100644
--- a/WalletWasabi/Stores/BlockFilterSqliteStorage.cs
+++ b/WalletWasabi/Stores/BlockFilterSqliteStorage.cs
@@ -51,14 +51,16 @@ public static BlockFilterSqliteStorage FromFile(string dataSource, FilterModel?
 			using (SqliteCommand createCommand = connection.CreateCommand())
 			{
 				createCommand.CommandText = """
-					CREATE TABLE IF NOT EXISTS filter (
-						block_height INTEGER NOT NULL PRIMARY KEY,
-						block_hash BLOB NOT NULL,
-						filter_data BLOB NOT NULL,
-						previous_block_hash BLOB NOT NULL,
-						epoch_block_time INTEGER NOT NULL
-					)
-					""";
+				                            CREATE TABLE IF NOT EXISTS filter (
+				                               block_height INTEGER NOT NULL PRIMARY KEY,
+				                               block_hash BLOB NOT NULL,
+				                               filter_data BLOB NOT NULL,
+				                               previous_block_hash BLOB NOT NULL,
+				                               epoch_block_time INTEGER NOT NULL
+				                            );
+				                            CREATE INDEX IF NOT EXISTS idx_blocks_height ON filter(block_height);
+				                            CREATE INDEX IF NOT EXISTS idx_blocks_hash ON filter(block_hash);
+				                            """;
 				createCommand.ExecuteNonQuery();
 			}
 
@@ -135,6 +137,37 @@ public IEnumerable<FilterModel> Fetch(uint fromHeight, int limit = -1)
 		}
 	}
 
+	/// <summary>
+	/// Returns <paramref name="n"/> filters after <paramref name="blockHash"/> in height.
+	/// Returns empty enumerable if <paramref name="blockHash"/> is not found
+	/// </summary>
+	public IEnumerable<FilterModel> FetchNewerThanBlockHash(uint256 blockHash, int n)
+	{
+		using SqliteCommand command = Connection.CreateCommand();
+		command.CommandText = """
+		                      WITH target_block AS (
+		                          SELECT block_height
+		                          FROM filter
+		                          WHERE block_hash = $blockHash
+		                      )
+		                      SELECT *
+		                      FROM filter
+		                      WHERE block_height > (SELECT block_height FROM target_block)
+		                      ORDER BY block_height ASC
+		                      LIMIT $n;
+		                      """;
+		command.Parameters.AddWithValue("$blockHash", blockHash.ToBytes(lendian: true));
+		command.Parameters.AddWithValue("$n", n);
+
+		using SqliteDataReader reader = command.ExecuteReader();
+
+		while (reader.Read())
+		{
+			FilterModel filter = ReadRow(reader);
+			yield return filter;
+		}
+	}
+
 	/// <summary>
 	/// Returns last <paramref name="n"/> filters from the database table.
 	/// </summary>
@@ -153,6 +186,19 @@ public IEnumerable<FilterModel> FetchLast(int n)
 		}
 	}
 
+
+	public int GetBestHeight()
+	{
+		using SqliteCommand command = Connection.CreateCommand();
+		command.CommandText = "SELECT MAX(block_height) FROM filter";
+		using SqliteDataReader reader = command.ExecuteReader();
+
+		return reader.Read() ?
+			reader.GetInt32(0) :
+			0;
+	}
+
+
 	/// <summary>
 	/// Removes the filter with the highest height from the database table.
 	/// </summary>