How to create recurring document template? How to run recurring document and what date should normally put to run it and what are the steps for Interest Calculations?

For Recurring document template you can use the following T.Codes

FBD1 - Creation of recurring document
FBD2 - Change recurring document (This is for changing of amount and recurring periods)
FBD3 - Display recurring document
F.14 - Posting of recurring document
F.15 - Display of recurring document

For Diff. run schedule recurring documents you can use this T.Codes

OBC1 - Creation of Diff. Run schedule Recurring document
OBC2 - Enter run dates for Recurring document
F.14 & F.15 steps are same

Steps For Interest Calculation you can use this following T.Codes :

OB59 - Define valuation method
OBA1 - Preapare automatinc postings for foreign currency valuation
FS00 - Assign exchange rate different key in loan a/c
F.05 - Foreign currencty revaluation
OBAA - Prepare account balance interest calculation
OBAc - Define reference interest rate
OB81 - Define time dependent terms
OB83 - Enter interest value
OBV2 - Assignmen of accounts for automatic
F.52 - Interest calculation

SAP FI Tips by: Janaka

How to calculate Customer Interest Calculation? - Aparna Sekhar

Interest calculation:

1. Define terms of payments:
T.code: OBB8 
path: img ->fin. accting -> AP AR :-> Business transactions :->outgoing invoice and credit memo :->
maintain terms of payment

2. Define Interest Cal indicators / type:
T.code: ob46
path: img ->fin. accting -> AP AR :-> Business transactions :-> interest calculation global settings :-> define interest cal types
Here in int cal type select 'p' for int cal on line items

3. Make Interest Indicator Available to Interest Run
Program:
T.Code: ob82
path: img ->fin. accting -> AP AR :-> Business transactions :-> interest calculation global settings :-> prepare int. on arreas

4. Create Reference Interest Rate:
T.code: OBAC
path: img ->fin. accting -> AP AR :-> Business transactions :-> interest calculation :-> interest calculation -> define reference interest rate

5. Assign interest indicators to ref. int rate 
or define time dependant terms:
T.code: ob81
path: img ->fin. accting -> AP AR :-> Business transactions :-> interest calculation :-> interest calculation -> define time dependant terms 
Here in sequence # always use 1 for line item interest

6. Interest calculation account assignment:
Here we will mention how and which accounts the interest program should post.
T.code: obv1
path: img ->fin. accting -> AP AR :-> Business transactions :-> interest calculation :-> interest posting -> prepare interest on arreas calculation (customers)

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