Bookkeeping Catch Up: Reconciling When You're Months Behind

If you're months behind, start from the last balance you know was right, then reconcile one month at a time, oldest first, until you reach today. Batch the routine transactions, keep a running list of anything you can't explain, and don't let that list stop you moving forward. Six months of bookkeeping catch up is usually a weekend or a few evenings, not the ordeal it feels like from the outside.

First, a bit of reassurance

Sam is a mobile hairdresser in Glasgow. She last reconciled her business account on 31 Mar 2026. It's now early Oct 2026, and she's been avoiding the books since around Easter.

She feels terrible about it. She shouldn't. Falling behind is one of the most common things that happens to busy owners, especially in the first couple of years. The work is mostly mechanical. It's the dread that takes the time.

So let's turn the dread into a plan.

Step 1: Find your anchor point

You need one balance you trust. That's the closing balance of the last period you properly reconciled.

For Sam, that's 31 Mar 2026. Her reconciliation report from then shows a closing balance of £4,316.80, and the bank statement agrees.

If you've never reconciled, or you're not sure the last one was right, go back to a date where you can prove the books and the bank agreed. The start of your financial year is a common choice, as long as the opening balance there was confirmed by your accountant.

Don't start from today and work backwards. You'll have no fixed point, and every difference will be impossible to pin to a month.

Step 2: Gather every statement in one place

Download statements for every month you're catching up on. For Sam, that's Apr 2026 to Sep 2026: six months.

Get both:

• PDF statements, which show the official opening and closing balance for each period
• CSV exports, which are far easier to import or sort

If you're using an Open Banking bank feed, check how far back it has pulled transactions. How much history a connection can fetch varies, so for older months you may need to import a CSV instead. Don't mix the two for the same dates, or you'll get duplicates.

Also gather the paperwork: sales invoices, supplier bills, and any notes about odd payments. Receipts are nice to have but don't let missing ones hold you up.

Step 3: Estimate the size of the job

Knowing the size makes it feel smaller. Sam has roughly 95 transactions a month on her business account.

570 lines sounds a lot. But 72 of them are the same 12 direct debits six times over, and 384 are client payments that look almost identical. The genuinely fiddly ones are probably 50 or 60.

Step 4: Do one month at a time, oldest first

Start with Apr 2026. Reconcile it completely, agree the closing balance to the Apr 2026 statement, then move on to May 2026. Don't open May 2026 until Apr 2026 balances (or until you've parked its leftovers properly, see Step 6).

Why not do all six months in one go? Because if the six-month total is out by £83.20, you've got 570 transactions to search. If Apr 2026 alone is out by £83.20, you've got 95.

Each month's closing balance becomes the next month's opening balance. That chain is what gives you confidence that the whole period is right.

Step 5: Batch the boring stuff

Within each month, sort transactions by payee and clear the easy groups first:

1. Recurring direct debits. Same payee, same or similar amount, same category each month. Sam's 12 standing costs take minutes once she's done them for Apr 2026.
2. Client payments. Categorise as sales, or match to invoices if she raised them.
3. Supplier orders. Match to the wholesaler's invoices.
4. Fuel and parking. Usually obvious from the payee name.

Clearing the big, easy groups first does wonders for morale. You'll see the unreconciled count drop fast, and what's left is a short list rather than a wall.

Step 6: Keep an "unknowns" list, and keep moving

You will hit transactions you can't explain. A £42.00 transfer in from a name you don't recognise. A card payment to a company you've never heard of. A £150 cash withdrawal you can't remember.

Don't stop. Post each one to a suspense account with a clear note, and add it to a list:

Many unknowns sort themselves out as you work through later months. A mystery transfer in Apr 2026 might match an invoice you find in May 2026. Come back to the list at the end, and anything still unknown goes to your accountant with the context you've already gathered.

Step 7: Give yourself a time budget

Catch-up work expands to fill whatever time you give it. A rough budget for Sam:

The first month always takes longest. By the fourth, you'll know every regular payee by heart.

Step 8: Lock each month as you finish it

Once a month is reconciled, save the reconciliation report and lock the period. That stops you, at 10pm on Evening 4, accidentally editing Apr 2026 while trying to fix Aug 2026.

Things not to do

• Don't post one big adjusting entry to force six months to agree. It hides whatever went wrong.
• Don't delete transactions because they're old or confusing. If it's on the statement, it happened.
• Don't wait for every receipt. Categorise from what you know and attach receipts later if you find them.
• Don't try to also fix your categories from last year. One job at a time. Finish the catch-up first.

Staying caught up afterwards

The catch-up is the hard bit. Staying current is easy by comparison, as long as you change the habit that led to falling behind.

For most people, that means:

• A fixed 20-minute slot each week to review new transactions
• A monthly reconciliation on a set day, say the 5th
• Letting the bank feed bring transactions in, so you're reviewing rather than typing

If the honest answer is that you'll never enjoy doing it, that's fine too. Invite a bookkeeper in and let them keep it current.

How HelloBooks helps

You can connect your bank through Open Banking (most UK banks and cards are supported) and import CSV statements for older months the feed doesn't cover. Everything lands in a review list where you confirm or change categories.

The reconcile screen puts each statement line next to your ledger with an AI match suggestion, a confidence score and the reason for the match, which is a big help when you're facing 95 lines a month. Wrong match? Unmatch in one click. Each month gives you a reconciliation report (opening balance, cleared items, outstanding items, closing balance) as PDF or CSV, and you can lock each period as you sign it off.

One honest note on plans. The Free plan covers up to 200 transactions a year, which suits a very quiet business. A catch-up like Sam's, at around 95 a month, needs Pro (£14.99/month), which also adds AI auto-categorisation and unlimited bank connections. The pricing page has the details. And you can invite your bookkeeper or accountant into the same books, which helps when the unknowns list needs a second opinion. More on automated bookkeeping here.

FAQs

Should I reconcile the most recent month first?

No. Start from your last known good balance and work forward. Otherwise you have nothing fixed to reconcile against.

What if I can't get old bank statements?

Most banks let you download statements from online banking going back several years. If yours doesn't, ask the bank for copies. A CSV export is usually enough for the transactions, with the PDF to confirm balances.

How do I handle months where I mixed personal and business spending?

Record the personal items honestly rather than hiding them in expenses, and ask your accountant how they want them treated.

Is it worth paying a bookkeeper to catch up?

If you're more than a year behind, or the unknowns list is long, often yes. Your time might be better spent running the business.

Will my accountant be annoyed?

Accountants see late books all the time. They'll be much happier with six reconciled months and a short list of questions than with a bag of statements.

Pick your anchor date tonight. That's the hardest decision, and once it's made the rest is just one month after another.

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