Set VBA Conditional Format highlight cell not equals 0 and amend subtraction to formula

hrh_dash 

The line with the formula should probably be

ws.Range("G" & check + 3).Offset(0, 1).Formula = "=B" & receiptsLastrow & "-H2+H4"

Without seeing the workbook it's impossible to tell why the conditional formatting isn't applied.

P.S. Please indent your code consistently. It is very difficult to read it without proper indentation.

Sub checkcal()
    Dim check As Long
    Dim ws As Worksheet
    Dim receiptsLastrow As Long
    Dim paymentsLastrow As Long
    Dim contractbid As Range
    Dim vendortotal As Range
    Set ws = Sheet1
    check = ws.Cells(ws.Rows.Count, "G").End(xlUp).Row
    ws.Range("G" & check + 2).Value = "Check"
    ws.Range("G" & check + 3).Value = "Check receipts ties back to contract bid"
    ws.Range("G" & check + 4).Value = "Check payments ties back to vendor cost"
    receiptsLastrow = ws.Cells(ws.Rows.Count, "B").End(xlUp).Row
    paymentsLastrow = ws.Cells(ws.Rows.Count, "C").End(xlUp).Row
    If ws.Range("H1") = "Yes" Then
        ws.Range("G" & check + 3).Offset(0, 1).Formula = "=B" & receiptsLastrow & "-H2+H4"
        ws.Range("G" & check + 3).Offset(0, 1).NumberFormat = "#,##0.00"
        With ws.Range("G" & check + 3).Offset(0, 1) '<-- condition formatting to fill cell in red if cell value <> 0
            .FormatConditions.Delete
            .FormatConditions.Add Type:=xlCellValue, Operator:=xlNotEqual, _
             Formula1:="=0"
            With Selection.FormatConditions(1).Interior
                .Color = vbRed
            End With
        End With
        With ws.Cells
            Set vendortotal = .Find(What:="Total", After:=ActiveCell, LookIn:=xlValues _
                , Lookat:=xlPart, SearchOrder:=xlByRows, SearchDirection:=xlNext, _
                MatchCase:=False)
        End With
        ws.Range("G" & check + 4).Offset(0, 1).Formula = "=C" & paymentsLastrow & "-" & vendortotal.Offset(0, 3).Address(False, False)
        ws.Range("G" & check + 4).Offset(0, 1).NumberFormat = "#,##0.00"
        With ws.Range("G" & check + 4).Offset(0, 1) '<-- condition formatting to fill cell in red if cell value <> 0
            .FormatConditions.Delete
            .FormatConditions.Add Type:=xlCellValue, Operator:=xlNotEqual, _
             Formula1:="=0"
            With Selection.FormatConditions(1).Interior
               .Color = vbRed
            End With
        End With
    Else
        With ws.Cells
            Set contractbid = .Find(What:="Contract Bid (incl GST)", After:=ActiveCell, LookIn:=xlValues _
                , Lookat:=xlPart, SearchOrder:=xlByRows, SearchDirection:=xlNext, _
                MatchCase:=False)
        End With
        ws.Range("G" & check + 3).Offset(0, 1).Formula = "=B" & receiptsLastrow & "-" & contractbid.Offset(0, 1).Address(False, False)
        ws.Range("G" & check + 3).Offset(0, 1).NumberFormat = "#,##0.00"
        With ws.Range("G" & check + 3).Offset(0, 1) '<-- condition formatting to fill cell in red if cell value <> 0
            .FormatConditions.Delete
            .FormatConditions.Add Type:=xlCellValue, Operator:=xlNotEqual, _
             Formula1:="=0"
            With Selection.FormatConditions(1).Interior
                .Color = vbRed
            End With
        End With
        With ws.Cells
            Set vendortotal = .Find(What:="Total", After:=ActiveCell, LookIn:=xlValues _
                , Lookat:=xlPart, SearchOrder:=xlByRows, SearchDirection:=xlNext, _
                MatchCase:=False)
        End With
        ws.Range("G" & check + 4).Offset(0, 1).Formula = "=C" & paymentsLastrow & "-" & vendortotal.Offset(0, 3).Address(False, False)
        ws.Range("G" & check + 4).Offset(0, 1).NumberFormat = "#,##0.00"
        With ws.Range("G" & check + 4).Offset(0, 1) '<-- condition formatting to fill cell in red if cell value <> 0
            .FormatConditions.Delete
            .FormatConditions.Add Type:=xlCellValue, Operator:=xlNotEqual, _
             Formula1:="=0"
            With Selection.FormatConditions(1).Interior
                .Color = vbRed
            End With
        End With
    End If
End Sub