Historical transaction cleanup before a Cryptoworth migration
Eighteen months of accumulated transaction history does not normalize itself. Here is how we run a pre-implementation cleanup sprint.
Most crypto companies that hire an implementation partner are not setting up a subledger from scratch — they are migrating onto one after running for a year or two on spreadsheets and a portfolio tracker. The migration is not the work. The historical cleanup is.
What 'cleanup' actually means
Before any data enters Cryptoworth, it has to be complete and consistent. We run three passes:
Pass 1: completeness
Every wallet, every chain, every exchange — confirm the data we have matches what the chain says. Pull explorer histories, reconcile against the existing spreadsheets, find the gaps. Most engagements turn up at least one stale connection or one wallet that was never tracked.
Pass 2: classification
Group the historical activity into the categories that will be used going forward. Staking rewards, lending interest, swaps, bridge transfers, airdrops, gas. Decide for each what the accounting treatment is, document it, and apply consistently across history.
Pass 3: cost-basis reset
With cleanup done, compute opening cost basis per asset per wallet, using the chosen methodology. This is what gets loaded into Cryptoworth as the starting state. Get this wrong and every disposal from day one carries a basis error.
Timeline
A clean cleanup on a single-entity, 12-month history with under 5,000 transactions takes about two weeks. A messy cleanup on a multi-entity history with 30,000+ transactions takes 4–6 weeks. Build that into your migration timeline before you commit to a 'first close' date with the team.