Almost every Twin Ports cost comparison stops at the purchase price and the property tax bill. There is a third thing, it happens once, and it is the only part of the cross-border comparison where Minnesota charges a category of tax that Wisconsin simply does not have.
Minnesota taxes the sale and the loan. Wisconsin taxes the sale only.
The three charges, with verified rates
Minnesota deed tax: 0.0033 of the net consideration. Counties collect it when an instrument conveying Minnesota real property is presented for recording. Hennepin and Ramsey counties add an Environmental Response Fund tax of 0.0001; no other Minnesota county does. That means St. Louis County (Duluth, Hermantown, Proctor, the North Shore), Carlton County (Cloquet, Carlton, Esko, Wrenshall) and Lake County (Two Harbors, Silver Bay) all sit at the plain 0.0033.
Minnesota mortgage registry tax: 0.0023 of the debt secured. Counties collect it when a mortgage is presented for recording, and the Department of Revenue states plainly that the borrower is responsible for paying it. Same county picture: Hennepin and Ramsey add 0.0001, nobody else does.
Wisconsin real estate transfer fee: 30 cents per $100 of value, or fraction thereof, on every conveyance not exempted, under Wisconsin Statute 77.22. That is 0.003. The register of deeds collects it when the conveyance is submitted for recording, and the statute is explicit that a completed transfer return and collection of the fee are prerequisites to the conveyance being accepted for recording at all.
Note what is missing from that Wisconsin list. There is no mortgage registry tax. Financing a purchase in Wisconsin does not generate a state charge on the loan the way it does in Minnesota.
A worked example
Take a $300,000 purchase with a $240,000 mortgage, which is a realistic mid-market Twin Ports transaction on either side of the bay.
Buying in Duluth, or anywhere in St. Louis or Carlton County:
- Deed tax: 0.0033 × $300,000 = $990
- Mortgage registry tax: 0.0023 × $240,000 = $552
- Total state transfer charges: $1,542
Buying in Superior, or anywhere in Douglas County:
- Transfer fee: 0.003 × $300,000 = $900
- Mortgage registry tax: none
- Total: $900
A $642 difference on the same transaction. And the split matters more than the total, because the two charges land on different parties: the mortgage registry tax is the borrower's, so the buyer-side difference is the full $552.
These are the state-level transfer charges only. They are not your whole closing statement, which will also carry lender fees, title work, recording fees, prorated property taxes and prepaid escrows.
What is law and what is merely custom
This distinction matters and it is where a lot of published advice quietly misleads.
Law, and sourced above: the rates, the fact that counties collect at recording, that the Minnesota mortgage registry tax falls on the borrower, and that in Wisconsin a completed transfer return plus the fee are prerequisites to recording.
Custom, and negotiable: who pays the deed tax or the transfer fee. In both states this is a market convention that typically falls to the seller, and in both states it is a term of the purchase agreement rather than a rule. Wisconsin's statute contemplates both grantor and grantee in the return process; it does not settle who bears the cost between them. If someone tells you it is fixed, it is not. Ask your agent what is customary in the specific market and then read your own contract.
Also custom, and worth asking about: which party selects and pays for title insurance and the closing agent, and how those costs are split. These conventions differ between the two states and even between market segments, and they are real money.
Why this belongs in a cross-border decision
Not because it will change your mind. It probably will not: Superior's purchase prices run substantially below Duluth's, and a few hundred dollars at closing does not move against a five-figure price gap.
It belongs in the decision because it is a cash-at-closing item, and cash at closing is the constraint that actually stops transactions. A buyer stretching to a Duluth purchase should know that Minnesota will add a charge on the loan itself that a Wisconsin purchase would not, and should have that number in the budget before the closing disclosure arrives rather than after.
Two practical notes.
Refinancing. The Minnesota mortgage registry tax attaches to a mortgage being recorded, so it is not purely a purchase cost. Factor it into refinance math on the Minnesota side. Wisconsin owners do not face the equivalent.
Exemptions exist and they are numerous. Minnesota lists statutory exemptions for both taxes covering agricultural loans, affordable housing, tribal, religious and educational transfers, reverse mortgages and more. Wisconsin's transfer fee likewise has an exemption schedule. If your transaction is anything other than an ordinary arm's-length sale, ask rather than assume.
Where this fits with the rest of the cross-border picture
Closing costs are the one-time layer. Two others matter more over a long hold:
The recurring layer is property tax, where the two states apply relief at completely different points in the arithmetic and the only reliable method is pulling a specific parcel's prior-year bill. See How Property Taxes Actually Work in the Twin Ports.
The annual layer is income tax, and it contains the region's biggest and least-known trap: Minnesota and Wisconsin have no reciprocity agreement, so crossing the bridge for work means filing in both states. See The Cross-Border Math.
Sources: Minnesota Department of Revenue (deed tax, deed tax rate, mortgage registry tax, mortgage tax rate); Wisconsin Statute 77.22; Wisconsin Department of Revenue real estate transfer return. Rates and exemptions change and this is general information, not legal or tax advice. Confirm current figures and your own transaction's treatment with your closing agent, a licensed preparer, or the relevant department of revenue.