How to pull a balance date and master data date

Hi bweiland , here's a Power Query solution you can try out by pasting it in the Advance Editor:
1. Please make sure that you have two Tables: TableBalance and TableMasterData (This Table is being referred in the TableBalance Data as you'll see in the code). Thanks. Do let me know if you have any queries regarding the same.

Here's the code:

let
TableBalance = #table(
{"Account Number", "Date", "Balance"},
{
{1, #date(2025, 1, 31), 100},
{1, #date(2025, 1, 31), 100},
{1, #date(2025, 3, 31), 200}
}
),

Transform = Table.AddColumn(
TableBalance,
"Record",
each Table.FillDown(
Table.FromColumns(
Table.ToColumns(TableMasterData) & { { _[Date] } }
),
{"Column4"}
)
),

Record = Table.TransformColumns(
Transform,
{
"Record",
each Table.FirstN(
Table.Sort(
Table.SelectRows(
Table.AddColumn(_, "Check", each [Column4] >= [Column2]),
each [Check] = true
),
{ "Column2", Order.Descending }
),
1
)
}
),

Cols = List.Transform(
List.Skip(Table.ColumnNames(TableBalance)),
each "Master " & _
),

Table = Record,

Expand = Table.ExpandTableColumn(
Table,
"Record",
{"Column2", "Column3"},
Cols
)
in
Expand