The center of your firm. Every client, in order.
Nucleus brings every client into one place and looks for missing W-9s, new vendors with warning signs, miscoded expenses and bills that never arrived while you sleep. Open it in the morning and see exactly what needs you, most important first.
- Never changes your transactions
- 14 days free, no card
- Set up in 10 minutes
A second pair of eyes on every ledger
Six checks run on every client, every night, so the things that cause amended returns, penalties and awkward client calls get caught while they're still easy to fix.
Missing and incomplete W-9s
Spots every vendor you've paid without a W-9 on file. Upload one and Nucleus reads it, including line 3, and flags anything left blank.
New vendors with warning signs
Every new vendor is listed the night it appears, and flagged first if it shares an address or bank account with an employee, nearly copies another vendor's name, or got its first payment just under your approval limit.
Coding mistakes
Learns how each vendor is usually categorized and points out the transactions that don't fit, like software booked to Office Supplies.
Big items on the wrong side
Loan or owner money recorded as income, equipment written off as supplies, loan payments booked entirely as expense. The mistakes that swing profit by thousands.
Bills that never arrived
Learns each client's regular payments, like rent, software and the customer who pays every month, and tells you when one is missing. It also says when a client's books have fallen behind, before you close a month that isn't all there.
Duplicates, odd amounts and closed months
Catches the same bill entered twice, charges far outside a vendor's usual range, and edits to a month you already closed.
1099 screening
Works out which vendors probably need a 1099-NEC or 1099-MISC, and which are excluded, so January isn't a scramble.
From sign-up to first fix in three steps
- 01
Connect or upload
Connect a client's QuickBooks Online or Zoho Books with read-only access, or drop in CSV exports from any program, including Xero.
- 02
Nucleus checks every night
New transactions are reviewed against each client's own history. You get one prioritized list and a short email when something needs you.
- 03
Fix it in one click
Each item explains what's wrong and why it matters, then opens the exact record in QuickBooks, Zoho or Xero so you can fix it.
Upload a W-9. Nucleus checks every line.
Nucleus reads the form: the name on line 1, the tax classification on line 3, the address, the signature and the date. You confirm with one click. Anything blank or contradictory gets flagged, and a request for a corrected form lands on your to-do list.
- Works with fillable and printed-and-scanned forms
- Tells you which vendors need a 1099, and which form
- Taxpayer ID digits are never stored
Built to the standard your clients expect from their bank
Nucleus follows the controls banks are audited on: encryption, least privilege, step-up verification and a tamper-evident audit trail. Read the details, including how we handle a security incident.
Read-only, enforced in code
Nucleus can't change a single entry in QuickBooks, Zoho or Xero. Fixes stay in your hands. The one optional exception: an owner can let it attach W-9s to vendors.
Encryption with a key per file
AES-256 with a fresh key for every W-9. Master keys live in AWS KMS hardware and never leave it.
Tax IDs never stored
W-9s are read on our own servers. SSN and EIN digits are counted and then discarded, never saved or shared.
Tamper-evident activity log
Every view and change is recorded in a signed, chained log that even a database administrator can't quietly rewrite.
Two-step sign-in and roles
Authenticator codes for everyone, automatic sign-out, and owner, bookkeeper and read-only roles.
Each firm walled off
Your data is separated from every other firm by the database itself, and tested on every release.
Three sizes. Everything included.
Priced by the size of your firm, not per client or per seat. Every plan has every feature. Try it free for 14 days, no card needed.
Starter
Up to 25 clients
or $490 a year ($40.83/month): two months free
Start your free trialPractice
Up to 50 clients
or $990 a year ($82.5/month): two months free
Start your free trialFirm
Up to 250 clients
or $1,790 a year ($149.17/month): two months free
Start your free trialLarger firms
Over 250 clients
Terms that fit a firm your size, with everything included.
Email usEvery plan includes
- Unlimited team members
- QuickBooks Online and Zoho Books sync (Xero coming soon), plus CSV from anything else
- Every check: W-9s and 1099s, new and duplicate vendors, miscoded transactions
- W-9 reading and secure vendor upload links
- 1099 filing export and monthly client reports
- Two-step sign-in, encryption and a full activity log
- Email support
14 days free · No card needed · Cancel any time
Questions firms ask us
Will Nucleus change my clients' books?
Never. Nucleus only reads. When something needs fixing, the “Open in QuickBooks” or “Open in Zoho Books” button takes you straight to the record, and you make the change yourself.
Which accounting software does it work with?
QuickBooks Online and Zoho Books connect directly and sync every night. Direct connections to Xero are coming soon; until then, upload its CSV exports and Nucleus checks them the same way. For anything else, such as Wave, FreshBooks or desktop QuickBooks, upload CSV exports too.
Do you store Social Security numbers or EINs?
No. We read W-9s on our own servers to check the form is complete, but taxpayer ID digits are discarded immediately. Any tax ID column in an export is dropped before it's saved.
How long does setup take?
Most firms are reviewing their first client's results within ten minutes: create an account, add a client, then connect their books or upload a few exports.
Who on my team can see what?
Owners manage the team, settings and connections. Bookkeepers do the reviewing. Read-only members can look but not change anything, and the database enforces it.
How is Nucleus priced?
By the size of your firm, not per client and not per seat. Starter covers up to 25 clients, Practice up to 50, and Firm up to 250. Every plan has every feature and unlimited team members, so a growing firm never pays for features it already had.
What happens when I outgrow my plan?
Nucleus tells you when you add the client that doesn't fit, and an owner moves the firm up a plan from the Billing page. The change is prorated, so you only pay the difference for the rest of the period. You can move down the same way.
Is there a free trial?
Yes: 14 days with everything unlocked, and no card needed. If you subscribe during the trial, billing starts when the trial ends.
Can I cancel any time?
Yes. There's no contract. Cancel from the Billing page and you keep access until the end of the period you've paid for. You can export all your data whenever you like, even after cancelling.
Start the next close with nothing hiding in the books.
Set up your firm in minutes. Read-only, secure, and free to try.